# M.C.Q : Gaseous State ( 11 to 20 )

LEVEL – I
11. I , II , III are three isotherm respectively at T1 , T2 & T3 temperatures will be in order

(A) T1 = T2 = T3

(B) T1 < T2 < T3

(C) T1 > T2 > T3

(D) T1 > T2 = T3

12. NH3 is liquefied more easily than N2 . Hence

(A) a and b of NH3 > that of N2

(B) a(NH3) > a(N2) but b (NH3) < b(N2)

(C) a(NH3) < a(N2) but b (NH3) > b(N2)

(D) None

13. 0.2 mole sample of hydrocarbon CxHy yields after complete combustion with excess O2 gas , 0.8 mole of CO2, 1.1 mole of H2O. Hence hydrocarbon is

(A) C4H10

(B) C4H8

(C) C4H5

(D) C8H16

14. When 2 gm A gas is introduced into an evacuated flask kept at 25°C , the pressure is found to be 1 atm. If 3g of another gas B is then added to same flask, the total pressure becomes 0.5 atm. The ratio of molecular weights is

(A) 1:1

(B) 1:2

(C) 2:3

(D) 1:4

15. Air open vessel at 127°C is heated until 1/5th of air in it has been expelled. Assuming that the volume of vessel remains constant the temperature to which the vessel has been heated is

(A) 177°C

(B) 277°C

(C) 377°C

(D) 477°C

16. 3.2g S is heated if occupy a volume of 780 ml at 450°C and 723 mm pressure. Formula of sulphur is

(A) S2

(B) S

(C) S4

(D) S8

17. A gas cylinder containing cooking gas can withstand a pressure of 14.9 atm. The pressure gauge of cylinder indicates 12 atm at 27°C. Due to sudden fire in building the temperature starts rising. The temperature at which the cylinder will explode is.

(A) 42.5°C

(B) 67.8°C

(C) 99.5°C

(D) 25.7°C

18. A sample of gas is at 0°C. The temperature at which its rms speed of the molecule will be doubled is

(A) 103°C

(B) 273°C

(C) 723°C

(D) 818°C

19. 6 g each of the following gases at 87°C and 750 mm pressure are taken. Which of them will have the least volume

(A) HF

(B) HCl

(C) HBr

(D) HI

20. The temperature at which H2 has same rms speed (at 1 atm) as that of O2 at NTP is

(A) 37 K

(B) 17 K

(C) 512 K

(D) 27 K