By what factor does the average velocity of a gaseous molecule increase when the temperature (in kelvin) is doubled?

• 2.8

• 4.0

• 1.4

• 1.4

In Duma's method of estimation of nitrogen 0.35 g of an organic compound gave 55 mL of nitrogen collected at 300 K temperature and 715 mm pressure. The percentage composition of nitrogen in the compound would be

(Aqueous tension at 300 k = 15 mm)

• 16.45

• 17.45

• 14.45

• 14.45

A gas such as carbon monoxide would be most likely to obey the ideal gas law at

• high temperatures and low pressures

• low temperatures and high pressures

• high temperatures and high pressures

• high temperatures and high pressures

A bubble of air is underwater at temperature 15^o C  and the pressure 1.5 bar. If the bubbles rises to the surface where the temperature is 25^o C and the pressure is 1.0 bar, what will happen to the volume of the bubble?

• Volume will become greater by a factor of 1.6 

• Volume will become  greater by a factor of 1.1

• Volume will become  smaller by a factor of 0.70

• Volume will become  smaller by a factor of 0.70

The pressure exerted by 6.0 g of methane gas in a 0.03 m³ vessel at 129^o C is (Atomic masses C = 12.01, H = 1.01 and R = 8.314 JK^-1 mol^-1)

• 215216 Pa

• 13409 Pa

• 41648 Pa

• 41648 Pa

What  is the dominant intermolecular force or bond that must be overcome in converting liquid CH₃OH to a gas?

• Hydrogen bonding

• Dipole-dipole interaction

• Covalent bonds

• Covalent bonds

If a gas expands at constant temperature, it indicates that

• the kinetic energy of molecules decrease

• the pressure of the gas increases

• the kinetic energy of molecules remains the same

• the kinetic energy of molecules remains the same

What volume of oxygen gas (O₂) measured at 0^oC and 1 atm, is needed to burn completely 1 L of propane gas (C₃H₈)  measured under the same conditions?

• 7 L

• 6 L 

• 5 L 

• 5 L 

179.

20-litre container at 400 K contains CO₂(g) at pressure 0.4 atm and an excess of SrO (neglect the volume of solid SrO). The volume of the containers is now decreased by moving the movable piston fitted in the container. The maximum volume of the container, when pressure of CO₂ attains its maximum value, will be

Given that: SrCO₃ ⇌ SrO(s) + CO₂(g) kp = 1.6 atm)

• 5 litre

• 10 litre

• 8 litre

• 8 litre

The compressibility of a gas is less than unity at STP, therefore,

• V_m > 22.4 L

• V_m < 22.4 L

• V_m = 22.4

• V_m = 44.8 L