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JEE Main202311 Apr 2023Morning ShiftChemistryThermodynamics (C)Actual

Solid fuel used in rocket is a mixture of Fe 2 O 3 and Al (in ratio 1 : 2 ). The heat evolved ( kJ ) per gram of the mixture is _____ (Nearest integer) Given ΔH f 0 Al 2 O 3 = - 1700 kJ mol - 1 ΔH f 0 Fe 2 O 3 = - 840 kJ mol - 1 Molar mass of Fe , AI and O are 56 , 27 and 16 g mol – 1 respectively

Correct answer

0

Step-by-step solution

Molten iron can be prepared by alumino thermite process as shown below. Fe 2 O 3 + 2 Al → 2 Fe + Al 2 O 3 The iron oxide and aluminium metal ratio is 1 : 2 in the above reaction. Now, the Enthalpy of the reaction is equal to the difference of enthalpy of formation of products to the enthalpy of formation of reactants. ΔH reaction  0 = - 1700 + ( 840 ) Ratio of Fe 2 O 3 and Al =   160   :   54 =   2 . 96   in   214   gm   mixture ∴ ΔH ° 1 gm &#1

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