The heats of combustion of carbon and carbon monoxide are -393.5 and -283.5 kJ mol-1, respectively. The heat of formation (in kJ) of carbon monoxide per mole is :

Question

The heats of combustion of carbon and carbon monoxide are -393.5 and -283.5 kJ mol-1, respectively. The heat of formation (in kJ) of carbon monoxide per mole is : (A) 110.5 (B) 676.5 (C) -676.5 (D) -110.5

Tardigrade Admin · Accepted Answer

C ( g )+ O 2( g ) longrightarrow CO 2( g ) Δ H 1=-393.5 kJ / mol CO ( g )+(1/2) O 2( g ) longrightarrow CO 2( g ) Δ H 2=-283.5 kJ / mol C ( g )+(1/2) O 2( g ) longrightarrow CO ( g ) Δ H =Δ H 1-Δ H 2=-110 kJ / mol

Q. The heats of combustion of carbon and carbon monoxide are $- 393.5$ and $- 283.5 k J m o l^{- 1}$ , respectively. The heat of formation (in $k J$ ) of carbon monoxide per mole is :

110.5

676.5

-676.5

-110.5

$C_{(g)} + O_{2 (g)} ⟶ C O_{2 (g)} Δ H_{1} = - 393.5 k J / m o l$

$C O_{(g)} + \frac{1}{2} O_{2 (g)} ⟶ C O_{2} (g) Δ H_{2} = - 283.5 k J / m o l$

$C_{(g)} + \frac{1}{2} O_{2 (g)} ⟶ C O_{(g)} Δ H = Δ H_{1} - Δ H_{2} = - 110 k J / m o l$

Q. The heats of combustion of carbon and carbon monoxide are −393.5 and −283.5kJmol−1, respectively. The heat of formation (in kJ) of carbon monoxide per mole is :