Question

The enthalpy of dissociation of gaseous water per mole at 18°c and 1atm pressure is 241.75 kJ. Calculate it's value at 70°c if the heat capacities at constant pressure for water hydregen, and oxygen are 33.56, 28.83 and 29.12 JK mol​

Answer 1

Answer:

Correct option is

B

2.4 K

The relationship between the heat supplied, molar heat capacity at constant volume and the temperature change is q=m⋅C

p

ΔT

q=1kJ=1000J

Number of moles =m=

molecularweight

mass

=

18

100

Substitute values in the above expression.

1000=

18

100

×75×ΔT

Hence, the temperature change is 2.4 K.