C(s)+O2(g)→CO2(g);ΔH=−xkJ/mole
Q=CΔT=20kJ×2
40kJ heat is released for 2.4g of Carbon
For 1 mole 'Carbon' Q=2.440×12
=24400×12=200kJ/mole
Q=ΔE=ΔH=200kJ(∵Δng=0)
x=200
2.4g coal is burnt in a bomb calorimeter in excess of oxygen at 298K and 1atm pressure.
The temperature of the calorimeter rises from 298K to 300K. The enthalpy change during the combustion of coal is −xkJmol−1. The value of x is_____(Given : Heat capacity of bomb calorimeter 20.0kJK−1. Assume coal to be pure carbon)
Held on 26 Jul 2022 · Verified 6 Jul 2026.
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