Ionisation depends upon :

• pressure

• volume

• dilution

• none of these

Under isothermal condition, a gas at 300 K expands from 0.1 L to 0.25 L against a constant external pressure of 2 bar. The work done by the gas is:(Given that 1 L bar = 100 J)

• 5 kJ

• 25 J

• 30 J

• -30 J

In which case change in entropy is negative?

• Expansion of a gas at constant temperature

• Sublimation of solid to gas

• 2H(g) → H₂(g)

• Evaporation of water

For the reaction,

A (g) + 2B (g) → 2C (g) + 3D (g)

the change of enthalpy at 27°C is 19 kcal. The value of $∆$E is

• 21.2 kcal

• 17.8 kcal

• 18.4 kcal

• 20.6 kcal