For the given heat of reaction, (i) C ( s )+ O 2( g ) arrow CO 2( g )+97 kcal (ii) CO 2( g )+ C ( s ) arrow 2 CO ( g )-39 kcal the heat of combustion of CO ( g ) is

Question

For the given heat of reaction, (i) C ( s )+ O 2( g ) arrow CO 2( g )+97 kcal (ii) CO 2( g )+ C ( s ) arrow 2 CO ( g )-39 kcal the heat of combustion of CO ( g ) is (A) 68 kcal (B) -68 kcal (C) +48 kcal (D) None

Tardigrade Admin · Accepted Answer

Substracting equation from equation (i), we get;

C (s) + O_{2} (g) \to C O_{2} (g) + 97 k c a l

C O_{2} (g) + C (s) \to 2 CO (g) - 39 k c a l

we get

2 CO (g) + O_{2} \to 2 C O_{2} (g) + 136 k c a l

or,

CO (g) + 1/2 O_{2} (g) \to C O_{2} (g) + 68 k c a l

Heat of combustion

(Δ H) = - 68 k c a l

Q. For the given heat of reaction, (i) C(s)+O2​(g)→CO2​(g)+97kcal (ii) CO2​(g)+C(s)→2CO(g)−39kcal the heat of combustion of CO(g) is

68 kcal

-68 kcal

+48 kcal

None

Substracting equation from equation (i), we get; C(s)+O2​(g)→CO2​(g)+97kcal CO2​(g)+C(s)→2CO(g)−39kcal we get 2CO(g)+O2​→2CO2​(g)+136kcal or, CO(g)+1/2O2​(g)→CO2​(g)+68kcal Heat of combustion (ΔH)=−68kcal

Q. For the given heat of reaction,
(i) $C (s) + O_{2} (g) \to C O_{2} (g) + 97 k c a l$
(ii) $C O_{2} (g) + C (s) \to 2 CO (g) - 39 k c a l$
the heat of combustion of $CO (g)$ is