Question 8.3: CALCULATING THE AMOUNT OF HEAT RELEASED IN A REACTION How mu...

General Chemistry: Atoms First [1015060]
Chemistry

CALCULATING THE AMOUNT OF HEAT RELEASED IN A REACTION

How much heat in kilojoules is evolved when 5.00 g of aluminum reacts with a stoichiometric amount of $Fe_{2}O_{3}$ ?

$2 Al(s) + Fe_{2}O_{3}(s) → 2 Fe(s) + Al_{2}O_{3}(s)$ ΔH° = -852 kJ

STRATEGY
According to the balanced equation, 852 kJ of heat is evolved from the reaction of 2 mol of Al. To find out how much heat is evolved from the reaction of 5.00 g of Al, we have to find out how many moles of aluminum are in 5.00 g.

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