Answer : The enthalpy change or heat required is, 139.28775 KJ
Solution :
The conversions involved in this process are :
Now we have to calculate the enthalpy change.
where,
= enthalpy change or heat required = ?
m = mass of water = 45 g
= specific heat of solid water =
= specific heat of liquid water =
= specific heat of liquid water =
n = number of moles of water =
= enthalpy change for fusion = 6.01 KJ/mole = 6010 J/mole
= enthalpy change for vaporization = 40.67 KJ/mole = 40670 J/mole
Now put all the given values in the above expression, we get
(1 KJ = 1000 J)
Therefore, the enthalpy change is, 139.28775 KJ