Some Basic Concepts of Chemistry Mock Test – Class 11 Chemistry

1. A gas sample occupies at . The amount of gas present is:

2. A table shows complete dissociation of four salts.

The row that needs correction is:

3. A substance has molecular formula . Using atomic masses , , and , its molar mass is:

4. A sample of is diluted to . After complete dissociation, the concentration of ions is:

5. A food label mentions added minerals, a clinic uses an antiseptic, and a factory produces plastic containers. The shared reason these are chemistry-related is:

6. In a kitchen, cutting vegetables and cooking them give different kinds of changes. The better classification is:

7. A compound has empirical formula and molecular mass . Its molecular formula is:

8. A student writes that and must mean the same concentration. The best correction is:

9. A sample of is diluted to . The final concentration is:

10. The statement "all chemicals are dangerous" is scientifically weak because:

11. A data sheet lists , , , , , , and . The common feature of these symbols is that they are:

12. A standard solution has accepted concentration . Four sets of measurements are recorded.

The set that is precise but not accurate is:

13. An element has two isotopes with masses and , present in equal abundance. Its average atomic mass is:

14. The unit is best connected with:

15. A solution has concentration . What amount of solute is present in of this solution?

16. A candle is burning on a table. Wax near the flame melts first, and then wax vapour burns in air. The best interpretation is:

17. A aqueous solution of a non-electrolyte contains solute in water. The mole fraction of solute is closest to: use .

18. A shiny grey solid conducts electricity, has density , and slowly rusts in moist air. Which entry is a chemical property?

19. Use the graph description below.

Use . The slope of the graph is:

20. A graph is described below.

The slope of this graph is:

21. A transparent liquid is made by mixing ethanol and water completely. No separate layer is seen. The absence of layers mainly shows that the sample is:

22. Two pure samples of sodium chloride are analysed.

The best interpretation is:

23. A solution is prepared by mixing of methanol with enough water to make the final solution volume . Which setup correctly calculates the volume percent of methanol?

24. Consider the following statements about units used in chemistry:
I. is the base unit of mass.
II. is the base unit of amount of substance.
III. is the base unit of length.

25. A property record for a substance says: "white solid, soluble in water, melts at a definite temperature, does not burn easily." The entries about colour, solubility, and melting mainly describe:

26. A solution has density and is by mass in solute X. If molar mass of X is , the molarity of the solution is:

27. For , of and of are mixed. The limiting reagent is:

28. A density is reported as . What is the corresponding value in , using ?

29. A claim says, " of every gas occupies , whatever the conditions." The best correction is:

30. A lab note lists dilution data.

The row that needs correction is:

31. Use the arrangement described below: four cards are placed on a desk.
Card P: in a glass
Card Q: Air inside a balloon
Card R: Light from a lamp
Card S: A piece of copper wire
Which set contains only matter?

32. A solution is prepared by mixing of and of . Assuming volumes are additive and both salts dissociate completely, the final concentration of is:

33. A sample of and a sample of are kept at the same and . The correct comparison is:

34. A mass is reported as . The final zero is significant mainly because:

35. A compound has formula . The total number of oxygen atoms in one formula unit is:

36. A solution of is diluted from to . After dilution and complete dissociation, is:

37. A solution is by mass in sodium chloride. The mass of sodium chloride present is:

38. A solution is prepared by dissolving of and making the final volume . If molar mass of , the molarity is:

39. A sample contains of . The number of oxygen atoms present is:

40. A claim says, "Relative molecular mass and molar mass are the same kind of unit." The best correction is:

41. A final answer is written as . The main information given by the two zeros after is:

42. A student writes as . The value is equal, but the notation is not standard because:

43. Gay-Lussac's law of gaseous volumes should not be used directly for liquid water in the reaction because:

44. A calculator display shows . In scientific notation, this means:

45. The prefix is used in and . It represents:

46. A compact summary table for solution calculations is shown below.

The row that needs correction is:

47. A student uses the equation and claims that of gives of at the same and . The correction is:

48. The formula represents a compound rather than a mixture because:

49. A simple investigation compares how much salt dissolves in warm water and cold water. The chemistry idea most directly involved is:

50. A bowl contains sugar crystals and sand grains. The two solids can be separated by dissolving sugar in water, filtering off sand, and then evaporating the water. This method works mainly because: