A 2 m long tube closed at one end is lowered vertically into' water until the closed end is flush with the water surface. See figure below. Calculate the water level height in the tube. (Barometric pressure –1 atm =10 m of hydrostatic water head, Temperature = 25°C, Density of, water = 1.00 g/ml. Neglect water vapour pressure).

(1) 1.01 m

(2) 0.29 m

(3) 1.71^–m

(4) 0.92 m

At a certain temperature for which RT = 25 lit. atm. mol^–1, the density of a gas, in gm lit^–1, is d = 2.00P + 0.020 P², where P is the pressure in atmosphere. The molecular weight of the gas in gm mol^–1 is-

1. 25

2. 50

3. 75

4. 100

Themolecular radius for a certain gas = 1.25 A. What is a reasonable estimate of the magnitude of the van der Wails constant, b, for the gas?

(1) 0.98 × 10^–2 litre/mole

(2) 1.43 × 10^–2 litre/mole

(3) 1.97 × 10^–2 litre/mole

(4) 3.33 × 10^–2 litre/mole

The van der Waal's constant 'b' for N₂ and H₂ has the values 0.039 lit moil^–1 and 0.0266 lit mo1^–1. The density of solid N₂ is 1 g cm^–3. Assuming the molecules in the solids to be close packed with the same percentage void, the density of solid H₂ would be (in g cm^–3)

(1) 0.114

(2) 0.682

(3) 1.466

(4) 0.071

A certain gas effuses out of two different vessels A and B. A has a circular orifice while B has a square orifice of length equal to the radius of the orifice of vessel A. The ratio of rate of diffusion of the gas from vessel A to that from vessel B is

(1) π : 1

(2) 1 : π

(3) 1 : 1

(4) 3 : 2

If 10²³ gas molecules each having a mass of 10^–25 kg, placed in a 1 L container, moving with RMS speed of 10⁵cm/sec. then the total KE of gaseous molecules and pressure exerted by molecules, respectively are :

(1) 10 kJ, 3.33 × 10⁶ Pa

(2) 5 kJ, 3.33 × 10⁸ Pa

(3) 10 kJ, 3.37 × 10⁷ Pa

(4) 5 kJ, 3.33 × 10⁷ Pa

A sample of a given mass of a gas at a constant temperature occupies 95cm³ under a pressure of $9.962\times {10}^4{\mathrm{Nm}}^{-2}$. At the same temperature, the volume at a pressure of $10.13\times {10}^4{\mathrm{Nm}}^{-2}$ is [Bihar CEE 1992]

1. 190 cm³

2. 93 cm³

3. 46.5 cm³

4. 47.5 cm³

A gas occupied a volume of 250 ml at 700 mm Hg pressure and 25°C. An additional pressure is required to reduce the gas volume to its 4/5^th value at the same temperature is-

1. 225 mm Hg

2. 175 mm Hg

3. 150 mm Hg

4. 265 mm Hg

When the temperature of 23 ml of dry CO₂ gas is increased from 10° to 30°C at a constant pressure of 760 mm, the volume of gas becomes-

1. 7.7 ml

2. 25.5 ml

3. 24.6 ml

4. 69 ml

The volume of a gas is 100 ml at 100°C. If the pressure remains constant then the temperature at which the volume becomes 200 ml is-

1. 200°C

2. 473°C

3. 746°C

4. 50°C