Home
Class 12
CHEMISTRY
The standard heat of formation (Delta(f)...

The standard heat of formation `(Delta_(f)H_(298)^(0))` of ethane (in kJ/mol), if the heat of combustion of ethane, hydrogen and graphite are `-1560, -393.5` and `-286kJ/mol`, respectively is _______.

Text Solution

Verified by Experts

The correct Answer is:
`-192.5`
`2C(s) + 3H_(2)(g) rarr C_(2)H_(6)(g)`
`DeltaH_(f)^(@) (C_2H_6) = sum Delta H_(C )^(@)("reactants") - sum Delta H_(C )^(@) ("products")`
`=2 xx Delta H_(C )^(@)C (s) + 3Delta H_(C )^(@)H_(2)(g) - Delta H_(C )^(@) C_(2)H_(6) (g)`
`=2 xx (-286) + 3 xx (-393.5) - (-1560)`
`=-192.5 kJ`
Promotional Banner

Similar Questions

Explore conceptually related problems

The standard heat of formation (Delta_(f)H_(298)^(@)) of ethane (in kJ/mol), if the heat of combustion of ethane, hydrogen and graphite are -1560, -393.5 and -286" kJ/mol" ,respectively is

Calculate the enthalpy of formation of methane given that the enthalpies of combustion of methane, graphite and hydrogen are 890.2 KJ, 393.4 KJ and 285.7 KJ mol^(-1) respectively

Calculate the resonance enegry of isoprene (C_(5)H_(8)) from the data given. Standard Heats of combustion of isoprene, carbon and hydrogen are -3186, -393.5 , and -285.83 kJ mol^(-1) , respectively. Bond energies of C=C, C-C, C-H and H-H bonds are 615, 348, 413 and 435.8 kJ mol^(-1) respectively. Standard heat of sulbilmation of graphite is 718.3 kJ mol^(-1) .

The standard heat of formation of carbon disulphide (l) given that standard heat of combustion of carbon (s), sulphur (s) and carbon disulphide (l) are -393.3, -293.72 and -1108.76 KJ mol^(-1) respectively is