Question

What is the standard enthalpy change for the vaporization of 50g of water at 100°C, given that the molar enthalpy of vaporization of water is 40.7 kJ/mol?

Answer 1

To calculate the standard enthalpy change for the vaporization of 50g of water, we first need to determine the number of moles of water present. The molar mass of water  H2O  is 18.015 g/mol.Number of moles = mass / molar massNumber of moles = 50 g / 18.015 g/mol = 2.775 molesNow, we can use the molar enthalpy of vaporization to find the total enthalpy change.Standard enthalpy change = number of moles  molar enthalpy of vaporizationStandard enthalpy change = 2.775 moles  40.7 kJ/mol = 112.94 kJThe standard enthalpy change for the vaporization of 50g of water at 100C is approximately 112.94 kJ.