The enthalpy of a vaporisation of CCI₄ is 30.5 kJ mol^-1. Calculate the heat required for the vaporisation of 284g of CCI₄ at constant pressure (molar mass of CCI₄ =154 g mol^-1)

An ideal gas is allowed to expand against a constant pressure of 2 bar from 10 L to 50 L in one step. Calculate the amount of work done by the gas. If the same expansion were carried out reversibly, will the work done be higher or lower than the earlier case (given that 1 L bar = 100 J)?

Expansion of a gas in vacuum is called free expansion. Calculate the work done and the change in internal energy when 1L of ideal gas expands isothermally into vacuum until its total volume is 5 L?

18.0 g water completely vaporises at 100 ^oC and 1 bar pressure and the enthalpy change in the process is 40.79 KJ mol^-1. What  will be the enthalpy change for vaporising two moles of water under the same conditions? What is the standard enthalpy of vaporisation for water?

Although heat is path function but heats absorbed by the system under certain specific conditions is independent of path. what are those conditions? Explain when volume remains constant.