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Q.82 Solid fuel used in rocket is a mixture of Fe2O3 and Al (in ratio 1 : 2). The heat evolved (kJ) per gram of the mixture is ____ (Nearest integer) Given : ΔfH°(Al2O3) = −1700 kJ mol−1 ΔfH°(Fe2O3) = −840 kJ mol−1
- 1
- 2
- 3
- 4
Correct answer: 4
Solution
The reaction between Fe2O3 and Al produces Al2O3 and releases a significant amount of heat. By calculating the enthalpy change based on the stoichiometry of the reactants and their respective enthalpies of formation, we find that the heat evolved per gram of the mixture is approximately 4 kJ.
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