Given ; (i) C(s)+O2(g) → CO2(g) ; Δ H=-94.0 kcal (ii) H2(g)+(1/2)O2(g) → H2O(l); Δ H=-68.4 kcal (iii) CH4(g)+O2(g)→ CO2(g)+2H2O(l); Δ H=-212.4 kcal The heat of formation of CH4 is

Question

Given ; (i) C(s)+O2(g) → CO2(g) ; Δ H=-94.0 kcal (ii) H2(g)+(1/2)O2(g) → H2O(l); Δ H=-68.4 kcal (iii) CH4(g)+O2(g)→ CO2(g)+2H2O(l); Δ H=-212.4 kcal The heat of formation of CH4 is (A) -1 8 .4 kcal (B) +18.4 kcal (C) -443.2 kcal (D) +443.2 kcal

Tardigrade Admin · Accepted Answer

(i) C +O2 -> CO2 ; Δ H=-94.0 kcal (ii) H2 +(1/2) O2 -> H2O ; Δ H=-68.4 kcal] × 2 (iii) CH4 +2O2 -> CO2 +2H2O ; Δ H=-212.4 kcal On multiplying equation (ii) with 2, add equation (i) and subtract equation (iii), we get C+2H2 +2O2 → CO2 +2H2O ; Δ H=-230.8 kcal CH4+2O2 → CO2+2H2O ; Δ H=-212.4 kcal C +2H2 → CH4 ; Δ H=-18.4 kcal

Q. Given ;
(i) $C_{(s)} + O_{2 (g)} \to C O_{2 (g)}; Δ H = - 94.0 k c a l$
$(ii) H_{2 (g)} + \frac{1}{2} O_{2 (g)} \to H_{2} O_{(l)}; Δ H = - 68.4 k c a l$
$(iii) C H_{4 (g)} + O_{2 (g)} \to C O_{2 (g)} + 2 H_{2} O_{(l)}; Δ H = - 212.4 k c a l$
The heat of formation of $C H_{4}$ is

$- 18.4 k c a l$

$+ 18.4 k c a l$

$- 443.2 k c a l$

$+ 443.2 k c a l$

Q. Given ; (i) C(s)​+O2(g)​→CO2(g)​;ΔH=−94.0kcal (ii)H2(g)​+21​O2(g)​→H2​O(l)​;ΔH=−68.4kcal (iii)CH4(g)​+O2(g)​→CO2(g)​+2H2​O(l)​;ΔH=−212.4kcal The heat of formation of CH4​ is

−18.4kcal

+18.4kcal

−443.2kcal

+443.2kcal

Q. Given ;
(i) $C_{(s)} + O_{2 (g)} \to C O_{2 (g)}; Δ H = - 94.0 k c a l$
$(ii) H_{2 (g)} + \frac{1}{2} O_{2 (g)} \to H_{2} O_{(l)}; Δ H = - 68.4 k c a l$
$(iii) C H_{4 (g)} + O_{2 (g)} \to C O_{2 (g)} + 2 H_{2} O_{(l)}; Δ H = - 212.4 k c a l$
The heat of formation of $C H_{4}$ is

$- 18.4 k c a l$

$+ 18.4 k c a l$

$- 443.2 k c a l$

$+ 443.2 k c a l$