17.0 g of NH3 completely vapourises at $$-$$33.42$$^\circ$$C and 1 bar pressure and the enthalpy change in the process is 23.4 kJ mol$$-$$1. The enthalpy change for the vapourisation of 85 g of NH3 under the same conditions is _________ kJ.
For combustion of one mole of magnesium in an open container at 300 K and 1 bar pressure, $$\Delta$$CH$$\Theta $$ = $$-$$601.70 kJ mol$$-$$1, the magnitude of change in internal energy for the reaction is __________ kJ. (Nearest integer)
(Given : R = 8.3 J K$$-$$1 mol$$-$$1)
4.0 L of an ideal gas is allowed to expand isothermally into vacuum until the total volume is 2.0 L. The amount of heat absorbed in this expansion is ____________ L atm.
When 5 moles of He gas expand isothermally and reversibly at 300 K from 10 litre to 20 litre, the magnitude of the maximum work obtained is __________ J. [nearest integer] (Given : R = 8.3 J K$$-$$1 mol$$-$$1 and log 2 = 0.3010)