What is the thermal energy needed to vaporize 18.02g of water at 100°C? The Heat of Vaporization for water is 40.650 kJ/mol.
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Answer:
40.7 kJ
Explanation:
Applying,
q = c'n.................. Equation 1
Where q = Thermal Heat, c' = Heat of vaporization of water, n = number of mole of water.
But,
n = mass(m)/Molar mass(m')
n = m/m'............... Equation 2
Substitute equation 2 into equation 1
q = c'(m/m')............. Equation 3
Given: c' = 40.650 KJ/mol, m = 18.02 g
Constant: m' = 18 g/mol
Substitute into equation 3
q = 40.650(18.02/18)
q = 40.695 kJ
q ≈ 40.7 kJ