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ChemistryMediumNumerical2023 · 11 Apr Shift 1

Q52.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 ΔHf0Al2O3 = - 1700 kJ mol-1 ΔHf0Fe2O3 = - 840 kJ mol-1 Molar mass of Fe, AI and O are 56, 27 and 16 g mol – 1 respectively

What This Question Tests

The question involves calculating the heat evolved per gram of mixture using standard enthalpy of formation data and reaction stoichiometry.

Concepts Tested

Standard enthalpy of formationHess's LawStoichiometry in thermochemistry

Formulas Used

ΔH_reaction = ΣΔH_f(products) - ΣΔH_f(reactants)

Moles = mass / molar mass

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