ECAT Chemistry Gases

1. A real gas obeying Van der Wall’s equation will resemble ideal gas if the:

2. The deviation of a gas from ideal behavior is maximum at:

3. The temperature recorded by Kelvin scale is:

4. Choose the best example of diffusion of gases

5. This is a known fact that the molar volumes of different gases at S.T.P. are

6. Which of the following elements will have strongest Van deer Wall force of attraction between its molecules?

7. if pressure remains constant _______, to which temperature the volume of a gas will become twice to what it is at 0°C.

8. . Imagine a man is sitting in a room. The room is closed from all sides, no entry, no exit of any gas. If the room expand suddenly then

9. Equal masses of methane and oxygen are mixed in an empty container at 25°C. The fraction of total pressure exerted by oxygen is:

10. Which of the following will have the same number of molecules at S.T.P?

11. . According to Boyle’s law at constant temperature, the product of pressure and volume of a given mass of gas is:

12. The order of the rate of diffusion of gases NH₃,SO₂,CI₂ and CO is

13. How should the conditions be changed to prevent the volume of a given gas from expanding when its mass increased?

14. . If absolute temperature of a gas is doubled nd the pressure is reduced to one half, the volume of the gas will

15. The solvent is selected for crystallization of a substance on the basis of:

16. The top of funnel stem should touch the side of the beaker because

17. Sublimation is a process for the separation of:

18. Preparation of aspirin is carried out by the reaction of salicylic acid with

19. Slow cooling of hot saturated solution yields.

20. Gooch crucible is used in a suction filtering apparatus, because:

21. The process of filtration is used to:

22. Fluted filter paper is used for

23. A bottle of copper (II) oxide has been contaminated wit5h some solid, NaCI. How can NaCI be removed from the (II) oxide?

24. . A flask contains the liquids trichloromethane (chloroform) and H₂O They are separated using a
separating funnel. Which conclusion can be made form this observation alone?

25. . Solvent extraction method is particularly useful technique for separation when the product to be
separated is:

26. For smooth filtration one of the following precautions should be observed

27. A filtration process could be very time consuming if it was not added by a gentle suction
which is developed

28. . From which mixture can the fast substance be obtained by adding water stirring and filtering?

29. What method is used to remove insoluble solids from muddy water?

30. By increasing temperature the transition from a gas to an ionized gas gives free electrons called

31. A gas has non-ideal behavior at:

32. Consider the physical properties of the gases. Which of the following statements about particles of
gases is incorrect? The particles are

33. A pressure of 1Nm¯² is equal to:

34. All of the following statements are incorrect expect

35. At constant temperature, volume of given mass of gas is inversely proportional to pressure on it. This
statement is according to

36. Gases deviate from ideal behavior at high pressure. Which of the following is correct for non-ideality?

37. Which one is not postulated in the kinetic molecular theory among the followings?

38. A teacher told his student that air is a mixture. This is due to the reason that suddenly a student
raised his hand and said

39. A teacher told his student that air is a mixture. This is due to the reason that suddenly a student
raised his hand and said

40. . If pressure is increased from 2 atm to 4 atm on a gas then its volume will decrease from:

41. The gases suddenly ______ if these are allowed to expand

42. To measure the true pressure of a gas collected over water, the pressure due to water vapors is?

43. . Suppose that all the air of the earth were replaced by an ocean of mercury. How deep would this
ocean have to be to exert the same pressure as the air

44. Which of the following laws study the pressure-volume relationship of a gas at constant
temperature?

45. A room is closed from all side in which a person is sitting. There is no entry and no exit of any gas. If a
room expands suddenly then.