Gas.pdf

Gaseous State

1.

2.

Same mass of CH 4 and H 2 is taken in container.

(a) 1.21 / 1

(b) 1.46 / 1

The partial pressure caused by H 2 is[IIT 1989; CPMT 1996]

(c) 1.14 / 1

(d) 4 / 1

(a) 8 / 9

(b) 1 / 9

(c) 1 / 2

(d) 1

7.

The following graph illustrates

257

Which of the following volume (V) – temperature (T) plots represents the behaviour of one mole of an ideal gas at one atmospheric pressure[IIT Screening 200

[JIPMER 2000]

V(L) (22.4 L 273 K)

V

V(L)

(36.8 L 373 K)

(a)

(22.4 L 273 K)

(b) T(K)

Temp. (oC)

3.

V(L)

(a) Dalton's law

(b) Charle's law

(c) Boyle's law

(d) Gay-Lussac's law

If the pressure and absolute temperature of 2 litres of CO 2 are doubled, the volume of CO 2

(22.4 L 273 K)

would become

T(K) V(L)

(30.6 L 373 K)

(c) 8.

(28.6 L 373 K)

(22.4 L 273 K)

(d) T(K)

(14.2 L 373 K) T(K)

If the average velocity of N 2 molecule is 0.3 m / s

at 27 o C , then the velocity will be 0.6 m / s at[Pb. CET 2001] [CBSE PMT 1991]

4.

(a) 2 litres

(b) 4 litres

(c) 5 litres

(d) 7 litres

9.

What is kinetic energy of 1 g of O 2 at 47 o C [Orissa JEE 2004]

5.

(a) 1 .24  10 2 J

(b) 2 .24  10 2 J

(c) 1 .24  10 3 J

(d) 3 .24  10 2 J

The root mean square speeds at STP for the gases H 2 , N 2 , O2 and HBr are in the order

10.

[Pb. CET 1994; CBSE PMT 1991]

(b) 600 K

(c) 400 K

(d) 1800 K

Equal volumes of two gases which do not react together are enclosed in separate vessels. Their pressures at 100 mm and 400 mm respectively. If the two vessels are joined together, then what will be the pressure of the resulting mixture (temperature remaining constant) [CBSE PMT 1981] (a) 125 mm

(b) 500 mm

(c) 1000 mm

(d) 250 mm

A gas of volume 100 cc is kept in a vessel at pressure 10 4 Pa maintained at temperature 24 o C .

(a) H 2  N 2  O2  HBr

If now the pressure is increased to 10 5 Pa, keeping the temperature constant, then the volume of the gas becomes [AFMC 1992]

(b) HBr  O2  N 2  H 2 (c) H2  N 2  O2  HBr (d) HBr  O2  H 2  N 2 6.

(a) 1200 K

By what ratio the average velocity of the molecule in gas change when the temperature is raised from 50 to 200 o C [DCE 2003]

11.

(a) 10 cc

(b) 100 cc

(c) 1 cc

(d) 1000 cc

If a gas is expanded at constant temperature[IIT 1986] (a) The pressure increases

(b) The kinetic energy of the molecules remains the same

Gaseous State

12.

(c) The kinetic energy of the molecules decreases

(a) 1 : 2

(b) 1 : 32

(d) The number of molecules of the gas increases

(c) 1 : 2

(d) 1 : 4

253

The rate of diffusion of SO 2 and O 2 are in the ratio [Assam JET 1991; EAMCET 1980]

(SET -6)

1.

(a) N CH 4 = number of moles of CH 4 

N H 2 = number of moles of H 2  fraction partial pressure of H 2

3. 4.

m 2 is

(c)

8.

(a) Vrms 

V2  2V , T2  ? 

V1  V2

9.

3 3 1 nRT    8 .314  320 J . 2 2 32

10.

U H 2 : U N 2 : U O2 : U HBr 

2

:

1

:

20

1 32

:

1 81

UHBr  UO 2  U N 2  UH 2

6.

(Vav )1  (Vav )2

T1  T2

423 1.14  323 1

P1  P2 100  400   250 mm 2 2

(a) P1 V1  P2 V2 at constant T 10 4 .100  10 5  V2

is

V2  10 cc 11.

(b) Kinetic energy will also remain constant if Temperature is constant.

12.

(a)

(c) T1  150  273  423 K ; T2  50  273  323 K Hence,

2

300  V     2 V T2  

(d) When two vessels are joined together, the volume will be doubled hence effective pressure will be halved P

 1 . 24  10 J 1 (b) Vrms  m

1

T1 T2

T2  300  4  1200 K

2

5.

3 RT ; Vrms  T M

Given, V1  V , T1  300 K

m 2

compare it with Y = C + mx PV T P 2T  2lt   2lt (a) V 2  1 1 . 2  T1 P2 2 P T (a) K.E. 

V1 T1 T 22 .4  373   V2  V1 . 2   30 .6 L V2 T2 T1 273

7.

m 8 H2   2   9 m m m n H 2  n CH 4 9  16 2 16 (b) According to Charle's Law V  T Vt  Vo  Vot nH2

2.

m 16

***

rSO 2 rO2



M O2 M SO 2



32 1  64 2