Question

The enthalpy of combustion for CO₂ is - 393.5 kJ mol^-1. Calculate the heat released during the formation of 35.2 g CO₂ from carbon and oxygen.

Answer 1

C(s) + O₂(g)  → CO₂(g); ∆H = -393.5 kJ mol^-1 

Free energy released in the formation of 44g CO₂ 

= 393.5 kJ mol^-1 

∴ Energy released in the formation of 35.2 g CO₂ 

\( = \frac{393.5\times 35.2}{44} = 314.8\ kJ\)