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101. How does the atomic radius of alkaline earth metals change as we move down Group 2?
ⓐ. Atomic radius decreases
ⓑ. Atomic radius increases
ⓒ. Atomic radius remains the same
ⓓ. Atomic radius fluctuates
Correct Answer: Atomic radius increases
Explanation: As we move down Group 2, the atomic radius increases. This is due to the addition of electron shells, which increases the size of the atom. The increased number of shells causes the electrons to be farther from the nucleus, resulting in a larger atomic radius.
102. Which of the following alkaline earth metals has the smallest atomic radius?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) has the smallest atomic radius among the alkaline earth metals. As we move up Group 2, the atomic radius decreases due to the smaller number of electron shells. Magnesium has the fewest shells, making it smaller compared to calcium, strontium, and barium.
103. What is the trend in ionic radius for alkaline earth metals as we move down the group?
ⓐ. Ionic radius decreases
ⓑ. Ionic radius fluctuates
ⓒ. Ionic radius remains constant
ⓓ. Ionic radius increases
Correct Answer: Ionic radius increases
Explanation: The ionic radius of alkaline earth metals increases as we move down the group. This is because, as the atomic size increases, the ions formed by these metals ($M^{2+}$) also become larger due to the addition of electron shells, leading to an increase in ionic radius.
104. Why does the atomic radius increase as we move down Group 2?
ⓐ. The effective nuclear charge decreases
ⓑ. The number of electron shells increases
ⓒ. The electrons are more tightly held by the nucleus
ⓓ. The ionization energy increases
Correct Answer: The number of electron shells increases
Explanation: The atomic radius increases as we move down Group 2 because the number of electron shells increases. Each additional shell increases the size of the atom, even though the nuclear charge also increases. The increased number of shells results in greater electron shielding and a larger atomic radius.
105. What is the ionic radius trend for alkaline earth metals as we move from magnesium (Mg) to barium (Ba)?
ⓐ. Ionic radius decreases
ⓑ. Ionic radius fluctuates
ⓒ. Ionic radius remains constant
ⓓ. Ionic radius increases
Correct Answer: Ionic radius increases
Explanation: As we move from magnesium (Mg) to barium (Ba), the ionic radius increases. This is because the size of the cations ($M^{2+}$) increases as we move down Group 2, due to the addition of electron shells. The increase in ionic radius reflects the larger atomic size of the elements.
106. Which of the following alkaline earth metals has the largest atomic radius?
ⓐ. Calcium (Ca)
ⓑ. Magnesium (Mg)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Barium (Ba)
Explanation: Barium (Ba) has the largest atomic radius among the alkaline earth metals. As we move down Group 2, the atomic radius increases because the number of electron shells increases. Barium, being the heaviest alkaline earth metal, has the largest atomic radius.
107. How does the size of the $M^{2+}$ ion change as we move down Group 2?
ⓐ. The size of the $M^{2+}$ ion decreases
ⓑ. The size of the $M^{2+}$ ion increases
ⓒ. The size of the $M^{2+}$ ion remains constant
ⓓ. The size of the $M^{2+}$ ion fluctuates
Correct Answer: The size of the $M^{2+}$ ion increases
Explanation: As we move down Group 2, the ionic radius of the $M^{2+}$ ion increases. This is because, although the charge on the ion remains the same, the number of electron shells increases as we move to heavier alkaline earth metals, causing the ion to be larger.
108. Why does barium (Ba) have a larger atomic radius than magnesium (Mg)?
ⓐ. Barium has more protons in its nucleus
ⓑ. Barium has fewer electron shells than magnesium
ⓒ. Barium has more electron shells than magnesium
ⓓ. Barium has a stronger attraction between the nucleus and electrons
Correct Answer: Barium has more electron shells than magnesium
Explanation: Barium (Ba) has a larger atomic radius than magnesium (Mg) because barium has more electron shells. Magnesium has only three shells, while barium has five, which increases the atomic size as more electron shells are added. The increased shielding reduces the effective nuclear charge on the outermost electrons, allowing them to be farther from the nucleus.
109. Which of the following alkaline earth metals has the smallest ionic radius?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) has the smallest ionic radius among the alkaline earth metals. This is because it has the smallest atomic radius and fewer electron shells compared to the other alkaline earth metals, leading to a smaller ionic radius when it forms a $M^{2+}$ ion.
110. As we move down Group 2, which of the following trends is true regarding the atomic and ionic radii?
ⓐ. Both atomic and ionic radii decrease
ⓑ. Both atomic and ionic radii increase
ⓒ. Atomic radii increase while ionic radii decrease
ⓓ. Atomic radii remain constant while ionic radii increase
Correct Answer: Both atomic and ionic radii increase
Explanation: As we move down Group 2, both atomic and ionic radii increase. The addition of electron shells increases the size of the atoms and the resulting cations ($M^{2+}$), leading to larger atomic and ionic radii.
111. How does the ionization enthalpy of alkaline earth metals change as we move down Group 2?
ⓐ. Ionization enthalpy increases
ⓑ. Ionization enthalpy fluctuates
ⓒ. Ionization enthalpy remains constant
ⓓ. Ionization enthalpy decreases
Correct Answer: Ionization enthalpy decreases
Explanation: As we move down Group 2, the ionization enthalpy decreases. This occurs because the atomic size increases, and the outermost electrons are farther from the nucleus. The increased shielding effect from inner electrons reduces the attraction between the nucleus and the outer electrons, making it easier to remove them.
112. Which of the following elements has the highest ionization enthalpy in Group 2?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) has the highest ionization enthalpy in Group 2. Magnesium is the smallest alkaline earth metal, and its outer electrons are more tightly bound to the nucleus compared to heavier elements in the group, such as calcium, barium, and strontium.
113. What is the main reason for the decrease in ionization enthalpy as we move down Group 2?
ⓐ. The effective nuclear charge increases
ⓑ. The atomic size decreases
ⓒ. The atomic size increases
ⓓ. The number of protons increases
Correct Answer: The atomic size increases
Explanation: As we move down Group 2, the atomic size increases due to the addition of electron shells. This larger size results in a weaker attraction between the outermost electrons and the nucleus, making it easier to remove the outermost electron, which decreases ionization enthalpy.
114. Which of the following statements is true regarding ionization enthalpy in Group 2 elements?
ⓐ. It increases as we move down the group
ⓑ. It decreases as we move down the group
ⓒ. It remains constant across the group
ⓓ. It fluctuates unpredictably down the group
Correct Answer: It decreases as we move down the group
Explanation: The ionization enthalpy of Group 2 elements decreases as we move down the group because the outermost electrons are farther from the nucleus and are more shielded by inner electrons. This results in less energy being required to remove the outer electron.
115. Why does calcium (Ca) have a lower ionization enthalpy than magnesium (Mg)?
ⓐ. Calcium has a smaller atomic size
ⓑ. Calcium has more inner electrons
ⓒ. Calcium has a higher nuclear charge
ⓓ. Calcium has fewer electron shells
Correct Answer: Calcium has more inner electrons
Explanation: Calcium (Ca) has a lower ionization enthalpy than magnesium (Mg) because calcium has more electron shells, increasing the shielding effect of the inner electrons. The outer electrons in calcium are farther from the nucleus and are more shielded, making it easier to remove them compared to magnesium.
116. Which alkaline earth metal requires the least amount of energy to remove its outermost electron?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Barium (Ba)
Explanation: Barium (Ba) requires the least amount of energy to remove its outermost electron. As we move down Group 2, the atomic size increases, and the outermost electron becomes more loosely bound, requiring less energy to be removed. Barium, being the heaviest alkaline earth metal, has the lowest ionization enthalpy in the group.
117. How does the ionization enthalpy of alkaline earth metals compare to alkali metals?
ⓐ. Ionization enthalpy of alkaline earth metals is higher
ⓑ. Ionization enthalpy of alkaline earth metals is lower
ⓒ. Ionization enthalpy is the same for both groups
ⓓ. Ionization enthalpy fluctuates for both groups
Correct Answer: Ionization enthalpy of alkaline earth metals is higher
Explanation: The ionization enthalpy of alkaline earth metals is higher than that of alkali metals. This is because alkaline earth metals have two valence electrons, which are more tightly held due to the stronger nuclear charge, whereas alkali metals have only one electron, which is more easily removed.
118. What trend is observed for ionization enthalpy as we move from magnesium (Mg) to barium (Ba)?
ⓐ. Ionization enthalpy increases
ⓑ. Ionization enthalpy fluctuates
ⓒ. Ionization enthalpy remains the same
ⓓ. Ionization enthalpy decreases
Correct Answer: Ionization enthalpy decreases
Explanation: As we move from magnesium (Mg) to barium (Ba), ionization enthalpy decreases. This is due to the increase in atomic size as we move down the group, making the outer electrons easier to remove. The increasing shielding effect and greater distance from the nucleus also contribute to this decrease in ionization enthalpy.
119. Which of the following alkaline earth metals will have the lowest ionization energy?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Barium (Ba)
Explanation: Barium (Ba) has the lowest ionization energy among the alkaline earth metals. Due to its larger atomic size and increased shielding by inner electrons, the outermost electron is more easily removed, requiring the least energy compared to other elements in Group 2.
120. How does the ionization enthalpy trend affect the reactivity of alkaline earth metals?
ⓐ. Higher ionization enthalpy results in greater reactivity
ⓑ. Lower ionization enthalpy results in greater reactivity
ⓒ. Ionization enthalpy has no effect on reactivity
ⓓ. Ionization enthalpy affects only the melting point, not reactivity
Correct Answer: Lower ionization enthalpy results in greater reactivity
Explanation: As ionization enthalpy decreases, the reactivity of alkaline earth metals increases. Lower ionization enthalpy makes it easier for the metals to lose their outermost electrons, which increases their tendency to form cations and react with other elements, such as halogens and water.
121. How does the hydration enthalpy of alkaline earth metals change as we move down the group?
ⓐ. It increases for larger cations
ⓑ. It decreases for smaller cations
ⓒ. It remains constant for all alkaline earth metals
ⓓ. It decreases for larger cations
Correct Answer: It decreases for larger cations
Explanation: Hydration enthalpy decreases as we move down Group 2 because the ionic size increases. Smaller cations like $Mg^{2+}$ have higher hydration enthalpy due to their higher charge density, which leads to stronger interactions with water molecules. Larger cations like $Ba^{2+}$ have weaker interactions with water and lower hydration enthalpy.
122. Which of the following alkaline earth metals has the highest hydration enthalpy?
ⓐ. Calcium (Ca)
ⓑ. Strontium (Sr)
ⓒ. Magnesium (Mg)
ⓓ. Barium (Ba)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium ($Mg^{2+}$) has the highest hydration enthalpy among the alkaline earth metals. Being the smallest cation in Group 2, it has the highest charge density, leading to stronger interactions with water molecules, which results in higher hydration enthalpy.
123. How does hydration enthalpy relate to the ionic size of the alkaline earth metals?
ⓐ. Larger ions have higher hydration enthalpy
ⓑ. Smaller ions have lower hydration enthalpy
ⓒ. Smaller ions have higher hydration enthalpy
ⓓ. Hydration enthalpy is independent of ionic size
Correct Answer: Smaller ions have higher hydration enthalpy
Explanation: Smaller ions, such as $Mg^{2+}$, have higher hydration enthalpy because they have a higher charge density. This allows them to attract water molecules more strongly. Larger ions, like $Ba^{2+}$, have lower charge density and therefore lower hydration enthalpy.
124. Which of the following factors primarily determines the hydration enthalpy of a cation?
ⓐ. The atomic mass of the cation
ⓑ. The size of the cation
ⓒ. The charge of the cation
ⓓ. The electron configuration of the cation
Correct Answer: The size of the cation
Explanation: The hydration enthalpy of a cation is primarily determined by its size and charge. Smaller cations with a higher charge density interact more strongly with water molecules, resulting in higher hydration enthalpy. For example, $Mg^{2+}$ has a higher hydration enthalpy than $Ba^{2+}$ due to its smaller ionic size.
125. Which of the following alkaline earth metals will have the least hydration enthalpy?
ⓐ. Barium (Ba)
ⓑ. Calcium (Ca)
ⓒ. Strontium (Sr)
ⓓ. Magnesium (Mg)
Correct Answer: Barium (Ba)
Explanation: Barium ($Ba^{2+}$) has the least hydration enthalpy among the alkaline earth metals. The larger the cation, the lower the hydration enthalpy because the ionic size reduces the charge density, making the interaction with water molecules weaker.
126. What is the primary reason that smaller cations have higher hydration enthalpy?
ⓐ. They have lower ionization energy
ⓑ. They are able to form more bonds with water molecules
ⓒ. They have a larger atomic radius
ⓓ. They have a higher charge density
Correct Answer: They have a higher charge density
Explanation: Smaller cations have a higher charge density, meaning their positive charge is concentrated in a smaller volume. This results in a stronger attraction between the cation and water molecules, leading to higher hydration enthalpy. $Mg^{2+}$ is a good example of this trend.
127. How does hydration enthalpy affect the solubility of salts of alkaline earth metals?
ⓐ. Higher hydration enthalpy leads to lower solubility
ⓑ. Higher hydration enthalpy leads to higher solubility
ⓒ. Hydration enthalpy has no effect on solubility
ⓓ. Solubility depends only on temperature
Correct Answer: Higher hydration enthalpy leads to higher solubility
Explanation: Salts with smaller cations, which have higher hydration enthalpy, tend to be more soluble. The stronger interaction between the smaller cations and water molecules helps the salt dissociate more easily in solution. This is why salts like $MgCl_2$ are more soluble than those of larger cations like $BaCl_2$.
128. Which of the following alkaline earth metals has the lowest hydration enthalpy?
ⓐ. Calcium (Ca)
ⓑ. Magnesium (Mg)
ⓒ. Strontium (Sr)
ⓓ. Barium (Ba)
Correct Answer: Barium (Ba)
Explanation: Barium ($Ba^{2+}$) has the lowest hydration enthalpy because it is the largest cation in Group 2. Its lower charge density leads to weaker interactions with water molecules, making it the least hydrated compared to smaller alkaline earth metal cations.
129. Which of the following statements is correct about the relationship between ionic size and hydration enthalpy for alkaline earth metals?
ⓐ. As ionic size increases, hydration enthalpy increases
ⓑ. As ionic size increases, hydration enthalpy decreases
ⓒ. Ionic size and hydration enthalpy are unrelated
ⓓ. Larger cations have higher charge density, resulting in higher hydration enthalpy
Correct Answer: As ionic size increases, hydration enthalpy decreases
Explanation: As the ionic size increases, the charge density decreases. This reduces the attraction between the cation and water molecules, leading to a decrease in hydration enthalpy. Smaller cations with higher charge densities, such as $Mg^{2+}$, have higher hydration enthalpy.
130. What trend is observed for hydration enthalpy as we move from magnesium (Mg) to barium (Ba)?
ⓐ. Hydration enthalpy fluctuates
ⓑ. Hydration enthalpy decreases
ⓒ. Hydration enthalpy remains the same
ⓓ. Hydration enthalpy increases
Correct Answer: Hydration enthalpy decreases
Explanation: Hydration enthalpy decreases as we move down the group because the ionic size increases, which lowers the charge density and weakens the attraction between the cation and water molecules.
131. Which of the following pairs exhibits a diagonal relationship in the periodic table?
ⓐ. Li and Na
ⓑ. Be and Mg
ⓒ. Li and Mg
ⓓ. Be and Al
Correct Answer: Be and Al
Explanation: The elements beryllium (Be) and aluminum (Al) exhibit a diagonal relationship due to their similar ionic sizes, charge densities, and chemical properties. The same applies to lithium (Li) and magnesium (Mg), but in this case, the correct pair showing a more evident diagonal relationship is Be and Al.
132. What is the main reason for the diagonal relationship between lithium (Li) and magnesium (Mg)?
ⓐ. Both have similar electronegativity
ⓑ. Both have similar atomic sizes
ⓒ. Both form similar compounds
ⓓ. Both are in the same group
Correct Answer: Both have similar atomic sizes
Explanation: The diagonal relationship between lithium (Li) and magnesium (Mg) arises from their similar atomic sizes, despite being in different groups. This leads to similar chemical behavior, such as their ability to form covalent compounds and exhibit amphoteric properties.
133. Which of the following properties is similar between lithium (Li) and magnesium (Mg)?
ⓐ. Both form only ionic compounds
ⓑ. Both are highly reactive with water
ⓒ. Both form amphoteric oxides
ⓓ. Both are good conductors of electricity
Correct Answer: Both form amphoteric oxides
Explanation: Both lithium (Li) and magnesium (Mg) form amphoteric oxides. Lithium forms $Li_2O$, which is amphoteric, and magnesium forms $MgO$, which also exhibits amphoteric behavior, reacting with both acids and bases.
134. Why does the diagonal relationship between beryllium (Be) and aluminum (Al) exist?
ⓐ. Both have similar atomic mass
ⓑ. Both have similar charge density and ionic radius
ⓒ. Both are in the same period
ⓓ. Both are metals
Correct Answer: Both have similar charge density and ionic radius
Explanation: Beryllium (Be) and aluminum (Al) exhibit a diagonal relationship because they have similar charge density and ionic radius, despite being in different groups. Their physical and chemical properties, such as the formation of covalent bonds and the ability to react with acids and bases, show strong similarities.
135. Which of the following compounds is formed by both lithium (Li) and magnesium (Mg)?
ⓐ. LiCl
ⓑ. MgCl₂
ⓒ. LiOH
ⓓ. Li₂O and MgO
Correct Answer: Li₂O and MgO
Explanation: Both lithium (Li) and magnesium (Mg) form oxides that are similar in nature, such as $Li_2O$ and $MgO$. Both oxides exhibit basic characteristics, and their amphoteric properties are also noteworthy, reacting with both acids and bases.
136. In terms of solubility, which of the following behaviors is shared by lithium (Li) and magnesium (Mg)?
ⓐ. Both form insoluble carbonates
ⓑ. Both form highly soluble sulfates
ⓒ. Both form highly soluble hydroxides
ⓓ. Both form soluble chlorides
Correct Answer: Both form insoluble carbonates
Explanation: Both lithium (Li) and magnesium (Mg) form insoluble carbonates, such as $Li_2CO_3$ and $MgCO_3$. Despite being in different groups, the similarity in the solubility behavior of their carbonates highlights their diagonal relationship.
137. What property of lithium (Li) and magnesium (Mg) is most similar due to their diagonal relationship?
ⓐ. Both have a low melting point
ⓑ. Both form highly basic solutions
ⓒ. Both are hard metals
ⓓ. Both form covalent bonds with non-metals
Correct Answer: Both form covalent bonds with non-metals
Explanation: Despite being metals, lithium (Li) and magnesium (Mg) exhibit a tendency to form covalent bonds with non-metals, such as in $Li_2O$ and $MgO$. This is in contrast to other alkali and alkaline earth metals, which typically form ionic bonds.
138. Which of the following is the key factor that contributes to the diagonal relationship between lithium (Li) and magnesium (Mg)?
ⓐ. Both have low ionization energies
ⓑ. Both have similar electronegativity
ⓒ. Both are highly reactive with air
ⓓ. Both form basic solutions
Correct Answer: Both have similar electronegativity
Explanation: Lithium (Li) and magnesium (Mg) have similar electronegativity values, which contribute to their diagonal relationship. This similarity allows them to exhibit comparable chemical behaviors, such as forming covalent bonds with non-metals and similar oxide properties.
139. What is one of the chemical properties that magnesium (Mg) and aluminum (Al) share due to their diagonal relationship?
ⓐ. Both form amphoteric oxides
ⓑ. Both form highly basic oxides
ⓒ. Both are highly reactive with water
ⓓ. Both form acidic oxides
Correct Answer: Both form amphoteric oxides
Explanation: Both magnesium (Mg) and aluminum (Al) form amphoteric oxides. Magnesium forms $MgO$, and aluminum forms $Al_2O_3$, both of which can react with both acids and bases. This property is characteristic of their diagonal relationship.
140. Which of the following similarities exists between lithium (Li) and magnesium (Mg)?
ⓐ. Both have a strong tendency to form ionic bonds
ⓑ. Both readily form covalent bonds
ⓒ. Both are highly reactive with oxygen
ⓓ. Both readily form complex ions
Correct Answer: Both readily form covalent bonds
Explanation: Despite being metals, lithium (Li) and magnesium (Mg) tend to form covalent bonds, especially when reacting with non-metals such as oxygen and halogens. This tendency to form covalent bonds is one of the reasons for their diagonal relationship.
141. Which of the following alkaline earth metals forms an oxide that is amphoteric in nature?
ⓐ. Strontium (Sr)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Magnesium (Mg)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) forms $MgO$, which is amphoteric. This means that magnesium oxide can react with both acids and bases. Other alkaline earth metal oxides like calcium oxide ($CaO$) and barium oxide ($BaO$) are basic in nature, while magnesium oxide is unique in its amphoteric behavior.
142. Which of the following forms peroxides when it reacts with oxygen?
ⓐ. Lithium (Li)
ⓑ. Magnesium (Mg)
ⓒ. Calcium (Ca)
ⓓ. Potassium (K)
Correct Answer: Lithium (Li)
Explanation: Lithium (Li) forms peroxides, such as $Li_2O_2$, when it reacts with oxygen. In contrast, other alkali and alkaline earth metals typically form oxides or superoxides depending on the conditions. Lithium’s small size and high charge density allow it to form peroxides more easily.
143. What is the product when barium (Ba) reacts with oxygen at higher temperatures?
ⓐ. Barium oxide ($BaO$)
ⓑ. Barium peroxide ($BaO_2$)
ⓒ. Barium superoxide ($BaO_2$)
ⓓ. Barium hydroxide ($Ba(OH)_2$)
Correct Answer: Barium peroxide ($BaO_2$)
Explanation: Barium (Ba) is a large, reactive metal that can stabilize the larger peroxide ion; when heated in oxygen, it readily forms barium peroxide ($BaO_2$).
144. Which alkaline earth metal forms a superoxide when it reacts with oxygen?
ⓐ. Lithium (Li)
ⓑ. Magnesium (Mg)
ⓒ. Potassium (K)
ⓓ. Calcium (Ca)
Correct Answer: Calcium (Ca)
Explanation: Calcium (Ca) reacts with oxygen to form calcium superoxide ($CaO_2$) under appropriate conditions. Superoxides are typically formed by alkali metals and some alkaline earth metals like calcium, which have a high tendency to form oxygen-rich compounds.
145. Which of the following alkaline earth metals does not form peroxides when it reacts with oxygen?
ⓐ. Barium (Ba)
ⓑ. Magnesium (Mg)
ⓒ. Calcium (Ca)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) does not form peroxides when it reacts with oxygen. Instead, magnesium typically forms magnesium oxide ($MgO$). Other alkaline earth metals such as barium, calcium, and strontium can form peroxides under certain conditions.
146. What is the general trend in the formation of oxides, peroxides, and superoxides as we move down Group 2?
ⓐ. The tendency to form superoxides decreases
ⓑ. The tendency to form oxides increases
ⓒ. The tendency to form superoxides increases
ⓓ. The tendency to form peroxides decreases
Correct Answer: The tendency to form superoxides increases
Explanation: As we move down Group 2, the tendency of alkaline earth metals to form superoxides increases. This is because the larger atoms have a lower ionization energy, which makes it easier for them to form superoxides in the presence of oxygen.
147. Which of the following reactions correctly shows the formation of a superoxide by potassium (K)?
ⓐ. $K + O_2 \rightarrow KO_2$
ⓑ. $K + O_2 \rightarrow K_2O$
ⓒ. $K + O_2 \rightarrow K_2O_2$
ⓓ. $K + O_2 \rightarrow KOH$
Correct Answer: $K + O_2 \rightarrow KO_2$
Explanation: Potassium (K) reacts with oxygen to form potassium superoxide ($KO_2$). Superoxides are commonly formed by alkali metals like potassium due to their larger atomic size and lower ionization energies, making it easier for them to stabilize the extra oxygen molecule.
148. Which of the following oxides is formed by the reaction of magnesium (Mg) with oxygen?
ⓐ. Magnesium hydroxide ($Mg(OH)_2$)
ⓑ. Magnesium peroxide ($MgO_2$)
ⓒ. Magnesium superoxide ($MgO_2$)
ⓓ. Magnesium oxide ($MgO$)
Correct Answer: Magnesium oxide ($MgO$)
Explanation: When magnesium (Mg) reacts with oxygen, it primarily forms magnesium oxide ($MgO$). Magnesium oxide is an example of a basic oxide that forms when magnesium burns in oxygen. Magnesium peroxide and superoxide are not typical products under normal conditions.
149. What is the product of the reaction between lithium (Li) and oxygen at elevated temperatures?
ⓐ. Lithium oxide ($Li_2O$)
ⓑ. Lithium peroxide ($Li_2O_2$)
ⓒ. Lithium superoxide ($LiO_2$)
ⓓ. Lithium hydroxide ($LiOH$)
Correct Answer: Lithium oxide ($Li_2O$)
Explanation: Lithium (Li) exhibits anomalous behavior due to its small size and primarily forms lithium oxide ($Li_2O$) when reacting with oxygen, unlike sodium which forms the peroxide.
150. Which of the following oxides is formed by the reaction of calcium (Ca) with oxygen?
ⓐ. Calcium oxide ($CaO$)
ⓑ. Calcium peroxide ($CaO_2$)
ⓒ. Calcium superoxide ($CaO_2$)
ⓓ. Calcium hydroxide ($Ca(OH)_2$)
Correct Answer: Calcium oxide ($CaO$)
Explanation: Calcium (Ca) reacts with oxygen to primarily form calcium oxide ($CaO$), which is a basic oxide. Calcium peroxide ($CaO_2$) and calcium superoxide ($CaO_2$) are also possible products but typically require specific conditions, such as higher temperatures or excess oxygen.
151. As we move down Group 2, what happens to the reactivity of alkaline earth metals with water?
ⓐ. Reactivity remains the same
ⓑ. Reactivity decreases
ⓒ. Reactivity increases
ⓓ. Reactivity fluctuates
Correct Answer: Reactivity increases
Explanation: As we move down Group 2, the reactivity of alkaline earth metals with water increases. This is because the ionization energy decreases and the atomic size increases, making it easier for the metals to lose their outermost electrons, which leads to increased reactivity.
152. What gas is released when alkaline earth metals react with water?
ⓐ. Oxygen (O₂)
ⓑ. Nitrogen (N₂)
ⓒ. Hydrogen (H₂)
ⓓ. Carbon dioxide (CO₂)
Correct Answer: Hydrogen (H₂)
Explanation: When alkaline earth metals react with water, they release hydrogen gas ($H_2$). For example, calcium reacts with water to produce calcium hydroxide ($Ca(OH)_2$) and hydrogen gas.
153. Which of the following alkaline earth metals reacts most vigorously with water?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Strontium (Sr)
ⓓ. Barium (Ba)
Correct Answer: Barium (Ba)
Explanation: Barium (Ba) reacts most vigorously with water among the alkaline earth metals. As we move down Group 2, the reactivity with water increases, and barium, being a larger metal, reacts more vigorously, releasing more hydrogen gas.
154. What is the product of the reaction between calcium (Ca) and water?
ⓐ. Calcium oxide ($CaO$)
ⓑ. Calcium hydroxide ($Ca(OH)_2$)
ⓒ. Calcium peroxide ($CaO_2$)
ⓓ. Calcium carbonate ($CaCO_3$)
Correct Answer: Calcium hydroxide ($Ca(OH)_2$)
Explanation: When calcium (Ca) reacts with water, it forms calcium hydroxide ($Ca(OH)_2$) and hydrogen gas ($H_2$). This reaction is typical of most alkaline earth metals, though the reactivity increases as we move down the group.
155. How does the rate of hydrogen gas production compare as we move down Group 2 in alkaline earth metals reacting with water?
ⓐ. It remains constant
ⓑ. It decreases
ⓒ. It increases
ⓓ. It fluctuates
Correct Answer: It increases
Explanation: As we move down Group 2, the rate of hydrogen gas production during reactions with water increases. This is due to the decreasing ionization energy and the increasing size of the atoms, which makes it easier for the outermost electrons to be removed and for the metal to react with water.
156. Which alkaline earth metal reacts with water at room temperature but less vigorously than others in the group?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) reacts with water, but the reaction is not as vigorous as that of calcium, strontium, or barium. Magnesium reacts slowly with cold water and more readily with hot water, producing magnesium hydroxide ($Mg(OH)_2$) and hydrogen gas ($H_2$).
157. Which of the following observations is true regarding the reaction of alkaline earth metals with water?
ⓐ. Only magnesium and calcium react with water to release hydrogen gas
ⓑ. All alkaline earth metals react with water, releasing hydrogen gas
ⓒ. Only the heavier alkaline earth metals react with water
ⓓ. Alkaline earth metals do not react with water
Correct Answer: All alkaline earth metals react with water, releasing hydrogen gas
Explanation: All alkaline earth metals, from magnesium (Mg) to barium (Ba), react with water to release hydrogen gas ($H_2$). The reactivity increases as we move down the group, with barium reacting the most vigorously.
158. How does the formation of hydroxides change as we move down Group 2?
ⓐ. The hydroxides become more soluble
ⓑ. The hydroxides become less soluble
ⓒ. The hydroxides remain equally soluble
ⓓ. The hydroxides are formed less readily
Correct Answer: The hydroxides become more soluble
Explanation: As we move down Group 2, the solubility of alkaline earth metal hydroxides in water increases. For example, calcium hydroxide ($Ca(OH)_2$) is more soluble than magnesium hydroxide ($Mg(OH)_2$), and barium hydroxide ($Ba(OH)_2$) is highly soluble.
159. Which of the following metals in Group 2 reacts with water to form an alkaline solution?
ⓐ. Calcium (Ca)
ⓑ. Magnesium (Mg)
ⓒ. Strontium (Sr)
ⓓ. Barium (Ba)
Correct Answer: Calcium (Ca)
Explanation: Calcium (Ca) reacts with water to form an alkaline solution of calcium hydroxide ($Ca(OH)_2$) and hydrogen gas ($H_2$). This reaction is typical of alkaline earth metals, but the reactivity increases as we move down the group.
160. What is the general trend for the reactivity of alkaline earth metals with water as we move down the group?
ⓐ. Reactivity decreases
ⓑ. Reactivity remains the same
ⓒ. Reactivity increases
ⓓ. Reactivity fluctuates
Correct Answer: Reactivity increases
Explanation: As we move down Group 2, the reactivity of alkaline earth metals with water increases. This is due to the decreasing ionization energy and the increasing size of the cations, which makes it easier for them to lose their outer electrons and react with water, producing hydrogen gas.
161. Which of the following alkaline earth metals forms an ionic hydride when it reacts with hydrogen?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Sodium (Na)
Correct Answer: Calcium (Ca)
Explanation: Calcium (Ca) reacts with hydrogen to form calcium hydride ($CaH_2$), an ionic hydride. Ionic hydrides are typically formed by the heavier alkali and alkaline earth metals, as they readily lose their outer electrons to form $M^{2+}$ cations.
162. What is the product of the reaction between sodium (Na) and hydrogen gas (H₂)?
ⓐ. Sodium oxide ($Na_2O$)
ⓑ. Sodium hydroxide ($NaOH$)
ⓒ. Sodium peroxide ($Na_2O_2$)
ⓓ. Sodium hydride ($NaH$)
Correct Answer: Sodium hydride ($NaH$)
Explanation: When sodium (Na) reacts with hydrogen gas (H₂), sodium hydride ($NaH$) is formed. This reaction results in the formation of an ionic hydride, where sodium donates an electron to form $Na^+$ and the hydrogen atoms form hydride ions ($H^-$).
163. Which of the following reactions demonstrates the formation of calcium hydride (CaH₂)?
ⓐ. $Ca + H_2 \rightarrow CaH_2$
ⓑ. $Ca + 2H_2 \rightarrow CaH_2$
ⓒ. $Ca + 2H_2 \rightarrow Ca_2H_2$
ⓓ. $Ca + 3H_2 \rightarrow CaH_3$
Correct Answer: $Ca + H_2 \rightarrow CaH_2$
Explanation: The reaction of calcium (Ca) with hydrogen gas ($H_2$) produces calcium hydride ($CaH_2$). This is a typical example of the formation of an ionic hydride, where calcium donates two electrons, forming $Ca^{2+}$ ions, and hydrogen accepts these electrons to form hydride ions ($H^-$).
164. Which of the following compounds is formed when lithium (Li) reacts with hydrogen?
ⓐ. Lithium hydroxide ($LiOH$)
ⓑ. Lithium oxide ($Li_2O$)
ⓒ. Lithium hydride ($LiH$)
ⓓ. Lithium peroxide ($Li_2O_2$)
Correct Answer: Lithium hydride ($LiH$)
Explanation: Lithium (Li) reacts with hydrogen to form lithium hydride ($LiH$). Lithium hydride is an ionic compound formed by the combination of $Li^+$ and $H^-$ ions. This is typical for alkali metals, which form hydrides when they react with hydrogen.
165. Which of the following alkaline earth metals does not form a hydride when it reacts with hydrogen?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Magnesium (Mg)
Explanation: Magnesium (Mg) does not typically form a hydride like the heavier alkaline earth metals. While magnesium reacts with hydrogen at high temperatures, it forms magnesium hydride ($MgH_2$) under specific conditions. However, for the most part, the lighter alkaline earth metals (like magnesium) are less likely to form hydrides compared to calcium, barium, and strontium.
166. What is the typical formula for an ionic hydride formed by alkaline earth metals?
ⓐ. $MH_2$
ⓑ. $M_2H_2$
ⓒ. $M_2H$
ⓓ. $M_3H_2$
Correct Answer: $MH_2$
Explanation: Ionic hydrides formed by alkaline earth metals have the general formula $MH_2$, where M is the metal and H is the hydride ion ($H^-$). For example, calcium hydride ($CaH_2$) and barium hydride ($BaH_2$) follow this formula.
167. Which of the following elements reacts with hydrogen to form an ionic hydride, showing the trend of increasing reactivity down Group 2?
ⓐ. Magnesium (Mg)
ⓑ. Calcium (Ca)
ⓒ. Barium (Ba)
ⓓ. Strontium (Sr)
Correct Answer: Barium (Ba)
Explanation: Barium (Ba) reacts most readily with hydrogen to form barium hydride ($BaH_2$), demonstrating the trend of increasing reactivity of alkaline earth metals with hydrogen as we move down the group. The larger atomic size and lower ionization energy of barium make it more reactive than magnesium, calcium, or strontium.
168. Which of the following is true about the formation of hydrides by alkaline earth metals?
ⓐ. All alkaline earth metals form molecular hydrides
ⓑ. Only the lighter alkaline earth metals form hydrides
ⓒ. Hydride formation decreases in reactivity as we move down the group
ⓓ. All alkaline earth metals form ionic hydrides
Correct Answer: All alkaline earth metals form ionic hydrides
Explanation: All alkaline earth metals form ionic hydrides when they react with hydrogen. The hydride ions ($H^-$) combine with metal cations to form ionic compounds like $CaH_2$, $BaH_2$, and $MgH_2$.
169. What is the product when magnesium (Mg) reacts with hydrogen at high temperatures?
ⓐ. Magnesium hydride ($MgH_2$)
ⓑ. Magnesium oxide ($MgO$)
ⓒ. Magnesium hydroxide ($Mg(OH)_2$)
ⓓ. Magnesium peroxide ($MgO_2$)
Correct Answer: Magnesium hydride ($MgH_2$)
Explanation: When magnesium (Mg) reacts with hydrogen gas at high temperatures, it forms magnesium hydride ($MgH_2$). This reaction produces an ionic hydride, where magnesium donates electrons and hydrogen accepts them to form $Mg^{2+}$ and $H^-$ ions.
170. What is the general trend of hydride formation across Group 2?
ⓐ. Hydride formation decreases as we move down the group
ⓑ. Hydride formation increases as we move down the group
ⓒ. Hydride formation remains constant
ⓓ. Hydride formation is independent of group trends
Correct Answer: Hydride formation increases as we move down the group
Explanation: The formation of hydrides increases as we move down Group 2. This is because the reactivity of alkaline earth metals with hydrogen increases as their atomic size increases and ionization energy decreases, making it easier for them to form ionic hydrides.
171. When sodium (Na) reacts with chlorine (Cl₂), what is the product formed?
ⓐ. Sodium chloride ($NaCl$)
ⓑ. Sodium perchlorate ($NaClO_4$)
ⓒ. Sodium oxide ($Na_2O$)
ⓓ. Sodium hypochlorite ($NaClO$)
Correct Answer: Sodium chloride ($NaCl$)
Explanation: When sodium (Na) reacts with chlorine (Cl₂), sodium chloride ($NaCl$) is formed. This is a typical ionic compound formed from the reaction of an alkali metal with a halogen. Sodium loses one electron to form $Na^+$, and chlorine gains that electron to form $Cl^-$, resulting in the formation of the ionic compound $NaCl$.
172. Which of the following represents the formation of calcium chloride from calcium (Ca) and chlorine (Cl₂)?
ⓐ. $Ca + Cl_2 \rightarrow CaCl$
ⓑ. $Ca + Cl_2 \rightarrow CaCl_2$
ⓒ. $Ca + 2Cl_2 \rightarrow CaCl_2$
ⓓ. $Ca + 2Cl_2 \rightarrow CaCl_4$
Correct Answer: $Ca + Cl_2 \rightarrow CaCl_2$
Explanation: When calcium (Ca) reacts with chlorine (Cl₂), it forms calcium chloride ($CaCl_2$). Calcium loses two electrons to form $Ca^{2+}$, and each chlorine atom gains one electron to form $Cl^-$, resulting in the ionic compound $CaCl_2$. This reaction is typical for alkaline earth metals reacting with halogens.
173. What is the product formed when magnesium (Mg) reacts with chlorine (Cl₂) at elevated temperatures?
ⓐ. Magnesium chloride ($MgCl_2$)
ⓑ. Magnesium oxide ($MgO$)
ⓒ. Magnesium peroxide ($MgO_2$)
ⓓ. Magnesium hydroxide ($Mg(OH)_2$)
Correct Answer: Magnesium chloride ($MgCl_2$)
Explanation: When magnesium (Mg) reacts with chlorine (Cl₂) at elevated temperatures, magnesium chloride ($MgCl_2$) is formed. Magnesium loses two electrons to form $Mg^{2+}$, and each chlorine atom gains one electron to form $Cl^-$, resulting in the ionic compound $MgCl_2$. This is a typical halide formation reaction.
174. What type of reaction occurs when sodium (Na) reacts with chlorine (Cl₂) to form sodium chloride ($NaCl$)?
ⓐ. Combination reaction
ⓑ. Decomposition reaction
ⓒ. Displacement reaction
ⓓ. Redox reaction
Correct Answer: Redox reaction
Explanation: The reaction between sodium (Na) and chlorine (Cl₂) to form sodium chloride ($NaCl$) is a redox reaction. Sodium undergoes oxidation by losing an electron to form $Na^+$, and chlorine undergoes reduction by gaining that electron to form $Cl^-$. This exchange of electrons makes the reaction a redox reaction.
175. Which of the following is the correct ionic equation for the formation of calcium chloride from calcium and chlorine?
ⓐ. $Ca^{2+} + 2Cl^- \rightarrow CaCl_2$
ⓑ. $Ca + Cl_2 \rightarrow Ca^{2+} + 2Cl^-$
ⓒ. $Ca \rightarrow Ca^{2+} + 2e^-$; $Cl_2 + 2e^- \rightarrow 2Cl^-$
ⓓ. $Ca + 2Cl_2 \rightarrow CaCl_2$
Correct Answer: $Ca \rightarrow Ca^{2+} + 2e^-$; $Cl_2 + 2e^- \rightarrow 2Cl^-$
Explanation: The ionic equation for the formation of calcium chloride from calcium and chlorine is:
$Ca \rightarrow Ca^{2+} + 2e^-$ (oxidation)
$Cl_2 + 2e^- \rightarrow 2Cl^-$ (reduction)
These half-reactions show that calcium loses two electrons, and chlorine gains two electrons to form chloride ions, resulting in the formation of calcium chloride ($CaCl_2$).
176. When barium (Ba) reacts with chlorine (Cl₂), which of the following compounds is formed?
ⓐ. Barium chloride ($BaCl_2$)
ⓑ. Barium perchlorate ($Ba(ClO_4)_2$)
ⓒ. Barium oxide ($BaO$)
ⓓ. Barium hydroxide ($Ba(OH)_2$)
Correct Answer: Barium chloride ($BaCl_2$)
Explanation: When barium (Ba) reacts with chlorine (Cl₂), barium chloride ($BaCl_2$) is formed. Barium loses two electrons to form $Ba^{2+}$, and each chlorine atom gains one electron to form $Cl^-$, resulting in the ionic compound $BaCl_2$. This reaction is typical for alkaline earth metals reacting with halogens.
177. Which of the following is the correct chemical equation for the formation of sodium chloride (NaCl) from sodium (Na) and chlorine (Cl₂)?
ⓐ. $Na + Cl_2 \rightarrow Na_2Cl$
ⓑ. $Na + Cl_2 \rightarrow NaCl$
ⓒ. $2Na + 2Cl_2 \rightarrow 2NaCl$
ⓓ. $2Na + Cl_2 \rightarrow 2NaCl$
Correct Answer: $2Na + Cl_2 \rightarrow 2NaCl$
Explanation: The correct chemical equation for the formation of sodium chloride from sodium and chlorine is $2Na + Cl_2 \rightarrow 2NaCl$. Two sodium atoms each lose one electron to form $Na^+$, and one chlorine molecule gains two electrons to form two chloride ions ($Cl^-$), resulting in the formation of sodium chloride.
178. What type of bond is formed in sodium chloride (NaCl) when sodium (Na) reacts with chlorine (Cl₂)?
ⓐ. Metallic bond
ⓑ. Covalent bond
ⓒ. Coordinate covalent bond
ⓓ. Ionic bond
Correct Answer: Ionic bond
Explanation: Sodium chloride (NaCl) is formed by the ionic bond between sodium (Na) and chlorine (Cl₂). Sodium loses an electron to form $Na^+$, and chlorine gains an electron to form $Cl^-$, resulting in the electrostatic attraction between the oppositely charged ions, which constitutes an ionic bond.
179. Which of the following reactions shows the correct stoichiometry for the formation of calcium chloride (CaCl₂) from calcium and chlorine?
ⓐ. $Ca + Cl_2 \rightarrow CaCl_2$
ⓑ. $Ca + 2Cl_2 \rightarrow CaCl_2$
ⓒ. $Ca + 2Cl_2 \rightarrow Ca_2Cl_2$
ⓓ. $Ca + 3Cl_2 \rightarrow CaCl_3$
Correct Answer: $Ca + Cl_2 \rightarrow CaCl_2$
Explanation: The correct stoichiometric equation for the formation of calcium chloride (CaCl₂) from calcium (Ca) and chlorine (Cl₂) is $Ca + Cl_2 \rightarrow CaCl_2$. Calcium reacts with chlorine in a 1:1 ratio to form calcium chloride.
180. Which of the following alkali metal halides is most commonly used as table salt?
ⓐ. Potassium chloride (KCl)
ⓑ. Sodium chloride (NaCl)
ⓒ. Lithium chloride (LiCl)
ⓓ. Cesium chloride (CsCl)
Correct Answer: Sodium chloride (NaCl)
Explanation: Sodium chloride (NaCl), commonly known as table salt, is the most commonly used halide compound. It is produced by the reaction of sodium with chlorine and is widely used in food preservation, seasoning, and various industrial applications.
181. Which of the following is a reason why lithium (Li) exhibits anomalous behavior compared to other alkali metals?
ⓐ. It has a higher atomic radius than sodium
ⓑ. It reacts more vigorously with water than sodium
ⓒ. It forms only ionic compounds
ⓓ. It has a small ionic size and high ionization energy
Correct Answer: It has a small ionic size and high ionization energy
Explanation: Lithium (Li) exhibits anomalous behavior because it has a small ionic size and high ionization energy compared to other alkali metals. This makes lithium’s chemical properties different from those of other alkali metals, and it behaves more similarly to alkaline earth metals like magnesium (Mg) in certain reactions.
182. Which of the following elements does lithium (Li) resemble due to its diagonal relationship?
ⓐ. Sodium (Na)
ⓑ. Magnesium (Mg)
ⓒ. Calcium (Ca)
ⓓ. Potassium (K)
Correct Answer: Magnesium (Mg)
Explanation: Lithium (Li) exhibits a diagonal relationship with magnesium (Mg) because of similarities in their ionic sizes, charge densities, and chemical properties. Both lithium and magnesium form covalent compounds, and their oxides exhibit amphoteric behavior, unlike other alkali and alkaline earth metals.
183. Which of the following is a typical behavior of lithium (Li) that distinguishes it from other alkali metals?
ⓐ. It forms only basic oxides
ⓑ. It reacts with water to form hydrogen gas but at a much slower rate
ⓒ. It forms covalent compounds with non-metals
ⓓ. It forms ionic halides with halogens
Correct Answer: It forms covalent compounds with non-metals
Explanation: Lithium (Li) forms covalent compounds with non-metals, which is an anomalous behavior compared to other alkali metals that generally form ionic compounds. Lithium’s small size and high ionization energy allow it to form covalent bonds with non-metals, such as in $Li_2O$ and $LiCl$.
184. Which of the following characteristics is shared by both lithium (Li) and magnesium (Mg) due to their diagonal relationship?
ⓐ. They both form highly basic oxides
ⓑ. They both form amphoteric oxides
ⓒ. They both react violently with water
ⓓ. They both form ionic compounds exclusively
Correct Answer: They both form amphoteric oxides
Explanation: Lithium (Li) and magnesium (Mg) share the characteristic of forming amphoteric oxides, such as $Li_2O$ and $MgO$. Amphoteric oxides can react with both acids and bases, a property that sets lithium and magnesium apart from other alkali and alkaline earth metals.
185. Which of the following compounds does lithium (Li) form that is similar to magnesium (Mg)?
ⓐ. Lithium carbonate ($Li_2CO_3$)
ⓑ. Lithium chloride ($LiCl$)
ⓒ. Lithium hydroxide ($LiOH$)
ⓓ. Lithium oxide ($Li_2O$)
Correct Answer: Lithium oxide ($Li_2O$)
Explanation: Lithium (Li) forms lithium oxide ($Li_2O$), which behaves similarly to magnesium oxide ($MgO$). Both lithium and magnesium form oxides that are amphoteric, meaning they can react with both acids and bases. This is a characteristic shared by lithium and magnesium due to their diagonal relationship.
186. What is one of the key reasons for the anomalous behavior of beryllium (Be) compared to other alkaline earth metals?
ⓐ. It is highly reactive with water
ⓑ. It forms basic oxides
ⓒ. It has a small ionic size and high ionization energy
ⓓ. It reacts slowly with acids
Correct Answer: It has a small ionic size and high ionization energy
Explanation: Beryllium (Be) exhibits anomalous behavior compared to other alkaline earth metals because of its small ionic size and high ionization energy. These properties make beryllium form covalent compounds and exhibit amphoteric oxide behavior, unlike other alkaline earth metals, which typically form ionic compounds.
187. Which of the following reactions demonstrates the anomalous behavior of lithium (Li) compared to sodium (Na)?
ⓐ. $Li_2O + H_2O \rightarrow 2LiOH$
ⓑ. $Li_2CO_3 + H_2O \rightarrow 2LiOH + CO_2$
ⓒ. $Na_2O + H_2O \rightarrow 2NaOH$
ⓓ. $Na_2CO_3 + H_2O \rightarrow 2NaOH + CO_2$
Correct Answer: $Li_2O + H_2O \rightarrow 2LiOH$
Explanation: Lithium (Li) forms lithium hydroxide ($LiOH$) from its oxide ($Li_2O$) in a way that is less typical for alkali metals. Sodium (Na), in contrast, forms sodium hydroxide ($NaOH$) from its oxide but does not show the same tendency to form amphoteric compounds. Lithium’s behavior is more similar to that of magnesium due to their diagonal relationship.
188. Why does lithium (Li) form covalent compounds unlike other alkali metals?
ⓐ. Due to its larger atomic size
ⓑ. Due to its lower ionization energy
ⓒ. Due to its higher electronegativity
ⓓ. Due to its high ionization energy and small ionic size
Correct Answer: Due to its high ionization energy and small ionic size
Explanation: Lithium (Li) forms covalent compounds due to its high ionization energy and small ionic size. These factors lead to stronger bonds with non-metals, resulting in covalent compounds such as $Li_2O$ and $LiCl$. Other alkali metals, which have lower ionization energies, tend to form ionic compounds instead.
189. Which of the following is a characteristic shared by both lithium (Li) and magnesium (Mg) due to their diagonal relationship?
ⓐ. They form basic oxides only
ⓑ. They form compounds with high ionic character
ⓒ. They both form covalent bonds with non-metals
ⓓ. They both react violently with water
Correct Answer: They both form covalent bonds with non-metals
Explanation: Both lithium (Li) and magnesium (Mg) form covalent bonds with non-metals, unlike other alkali and alkaline earth metals, which typically form ionic bonds. Lithium and magnesium exhibit a similar tendency to form covalent compounds, such as $Li_2O$ and $MgO$, due to their diagonal relationship.
190. Which of the following best describes the diagonal relationship between lithium (Li) and magnesium (Mg)?
ⓐ. They both form highly ionic compounds with halogens
ⓑ. They have similar ionic sizes, charge densities, and chemical behaviors
ⓒ. They both react similarly with oxygen to form peroxides
ⓓ. They both form basic hydroxides with water
Correct Answer: They have similar ionic sizes, charge densities, and chemical behaviors
Explanation: Lithium (Li) and magnesium (Mg) exhibit a diagonal relationship because they have similar ionic sizes, charge densities, and chemical behaviors. Both elements form covalent compounds with non-metals, and their oxides exhibit amphoteric behavior, which is uncommon for other alkali and alkaline earth metals.
191. Which of the following elements exhibits a diagonal relationship with beryllium (Be)?
ⓐ. Magnesium (Mg)
ⓑ. Sodium (Na)
ⓒ. Aluminum (Al)
ⓓ. Calcium (Ca)
Correct Answer: Aluminum (Al)
Explanation: Beryllium (Be) exhibits a diagonal relationship with aluminum (Al) due to similarities in their ionic sizes, charge densities, and chemical properties. Both Be and Al form amphoteric oxides and have comparable behavior when reacting with acids and bases, despite being in different groups.
192. What property of beryllium (Be) is most similar to that of aluminum (Al)?
ⓐ. Both form basic oxides
ⓑ. Both form ionic hydrides
ⓒ. Both react vigorously with water
ⓓ. Both form amphoteric oxides
Correct Answer: Both form amphoteric oxides
Explanation: Beryllium (Be) and aluminum (Al) both form amphoteric oxides, such as $BeO$ and $Al_2O_3$, which can react with both acids and bases. This is a key feature of their diagonal relationship, distinguishing them from other elements in their respective groups.
193. Which of the following compounds is formed by both beryllium (Be) and aluminum (Al)?
ⓐ. BeCl₂ and AlCl₃
ⓑ. BeO and Al₂O₃
ⓒ. BeH₂ and AlH₃
ⓓ. BeSO₄ and AlSO₄
Correct Answer: BeCl₂ and AlCl₃
Explanation: Both beryllium (Be) and aluminum (Al) form similar compounds such as $BeCl_2$ and $AlCl_3$. These compounds are covalent in nature, and their formation is a result of their diagonal relationship, where both Be and Al show a tendency to form covalent bonds rather than ionic compounds, unlike other members of their groups.
194. What is a key reason why beryllium (Be) exhibits anomalous behavior compared to other alkaline earth metals?
ⓐ. It forms only ionic compounds
ⓑ. It reacts with water to form hydrogen gas
ⓒ. It has a high ionization energy and small ionic size
ⓓ. It forms basic oxides exclusively
Correct Answer: It has a high ionization energy and small ionic size
Explanation: Beryllium (Be) exhibits anomalous behavior compared to other alkaline earth metals because it has a high ionization energy and small ionic size. These factors make it more similar to aluminum (Al), forming covalent compounds and exhibiting amphoteric properties, unlike other alkaline earth metals that form ionic compounds and basic oxides.
195. Which of the following is a characteristic shared by both beryllium (Be) and aluminum (Al)?
ⓐ. Both form only ionic oxides
ⓑ. Both form amphoteric oxides
ⓒ. Both form highly reactive halides
ⓓ. Both react violently with water
Correct Answer: Both form amphoteric oxides
Explanation: Both beryllium (Be) and aluminum (Al) form amphoteric oxides, such as $BeO$ and $Al_2O_3$. These oxides can react with both acids and bases, which is a key feature of their diagonal relationship. This behavior is not seen in other alkaline earth metals and is one of the main similarities between Be and Al.
196. Why does beryllium (Be) behave more like aluminum (Al) than magnesium (Mg)?
ⓐ. Due to the similar atomic radii of Be and Al
ⓑ. Due to the high electronegativity of Be and Al
ⓒ. Due to the similar charge density of Be and Al
ⓓ. Due to the similar reactivity of Be and Al with halogens
Correct Answer: Due to the similar charge density of Be and Al
Explanation: Beryllium (Be) behaves more like aluminum (Al) than magnesium (Mg) due to their similar charge density. Both Be and Al have small ionic sizes and high charge densities, leading to comparable chemical behavior, such as the formation of covalent compounds and amphoteric oxides, unlike magnesium (Mg), which behaves more ionic.
197. Which of the following elements has properties more similar to beryllium (Be) than to magnesium (Mg)?
ⓐ. Aluminum (Al)
ⓑ. Calcium (Ca)
ⓒ. Sodium (Na)
ⓓ. Potassium (K)
Correct Answer: Aluminum (Al)
Explanation: Aluminum (Al) shares many properties with beryllium (Be), such as forming amphoteric oxides and covalent compounds. This similarity arises from their diagonal relationship, where both elements exhibit behaviors typical of smaller, highly charged metals, in contrast to the larger, more ionic alkaline earth metals like magnesium and calcium.
198. Which of the following statements about beryllium (Be) and aluminum (Al) is true?
ⓐ. Both form only basic oxides
ⓑ. Both form covalent halides
ⓒ. Both react with oxygen to form superoxides
ⓓ. Both are highly reactive with water
Correct Answer: Both form covalent halides
Explanation: Both beryllium (Be) and aluminum (Al) form covalent halides, such as $BeCl_2$ and $AlCl_3$. This is a key feature of their diagonal relationship. Unlike other members of their respective groups, Be and Al tend to form covalent rather than ionic compounds due to their small ionic sizes and high charge densities.
199. What happens when beryllium (Be) reacts with acids?
ⓐ. It forms only basic salts
ⓑ. It forms neutral salts
ⓒ. It forms amphoteric salts
ⓓ. It forms acidic salts
Correct Answer: It forms amphoteric salts
Explanation: Beryllium (Be) forms amphoteric salts when it reacts with acids. This is due to the amphoteric nature of $BeO$ and $Be(OH)_2$, which can react with both acids and bases. This property is a result of its diagonal relationship with aluminum (Al).
200. Which of the following is the main reason for the diagonal relationship between beryllium (Be) and aluminum (Al)?
ⓐ. Similar electronegativity
ⓑ. Similar atomic radii
ⓒ. Both form only ionic compounds
ⓓ. Both have a similar ionization enthalpy
Correct Answer: Both have a similar ionization enthalpy
Explanation: Beryllium (Be) and aluminum (Al) share a diagonal relationship because they have similar ionization enthalpy. Both elements have relatively high ionization energies, which influences their ability to form covalent bonds and amphoteric oxides, as opposed to the more typical ionic behavior of other alkaline earth metals and other metals in their groups.
Welcome to Class 11 Chemistry MCQs – Chapter 10: The s-Block Elements (Part 2). In this section, we dive deeper into the reactivity of alkali and alkaline earth metals and their important compounds. This part builds on the basics and helps you solidify your understanding for JEE, NEET, and Board exams.
Topics covered in Part 2 (100 MCQs)
- Alkali metal reactions with water, oxygen, and halogens
- Alkaline earth metal reactions and their compounds like calcium oxide and magnesium hydroxide
- Solubility trends of salts in water, including common applications
- 👉 Total MCQs in this chapter: 359 (100 + 100 + 100 + 59)
- 👉 This page: Second set of 100 solved MCQs
- 👉 Next: Continue with Part 3