Question

For the reaction 2 Fe 2 O 3 ⟶ 4 Fe + 3 O 2 Δ H ∘ rxn = + 824.2 kJ / mol the decomposition of 44.0 g of Fe2O3 results in the absorption of 114 kJ of heat. the absorption of 18100 kJ of heat. the release of 227 kJ of heat. the absorption of 227 kJ of heat. the release of 18100 kJ of heat. the release of 114 kJ of heat.

Answer 1

- results in the absorption of 114 kJ of heat

Step-by-step explanation:

2 Fe 2 O 3 ⟶ 4 Fe + 3 O 2 Δ H ∘ rxn = + 824.2 kJ / mol

Molar mass of Fe 2 O 3 = 159.69 g/mol

From the reaction above, 2 mol of Fe 2 O 3 has heat change of + 824.2 kJ / mol.

1 mol = 159.69 g

x mol = 44.0 g

x = 44 / 156.69 = 0.2808mol

0.2808 mol would have x ?

2 = 824.2

0.2808 = x

x = (0.2808 * 824.2 ) / 2

x = + 115.72 kJ / mol.

A positive ∆H means that a reaction is endothermic as heat is absorbed from the surroundings to the system

This means the correct option is;

- results in the absorption of 114 kJ of heat