COMEDK · Chemistry · 6. Thermodynamics (C)
The heat of combustion of carbon to \(\text{CO}_2\) is -393.5 kJ \(\text{mol}^{-1}\).
The heat released on the formation of 35.2 g of \(\text{CO}_2\) by combustion of C is:
- A \(+620\ \text{kJ}\)
- B \(-315\ \text{kJ}\)
- C \(-325\ \text{kJ}\)
- D \(+215\ \text{kJ}\)
Answer & Solution
Correct Answer
(B) \(-315\ \text{kJ}\)
Step-by-step Solution
Detailed explanation
The combustion reaction of carbon is given by: \(\text{C(s)} + \text{O}_2\text{(g)} \rightarrow \text{CO}_2\text{(g)} \quad \Delta H = -393.5\ \text{kJ mol}^{-1}\) Molar mass of \(\text{CO}_2 = 12 + 2 \times 16 = 44\ \text{g mol}^{-1}\) Number of moles of \(\text{CO}_2\) formed…
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