How much energy is evolved during the formation of 98.7 g of Fe, according to the reaction below? Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(s) ΔH°rxn = -852 kJ How much energy is evolved during the formation of 98.7 g of Fe, according to the reaction below? Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(s) ΔH°rxn = -852 kJ 753 kJ 482 kJ 1.51 x 103 kJ 4.20 x 103 kJ 241 kJ

-753kJ of energy are involved

Explanation:

Based on the reaction:

Fe₂O₃(s) + 2 Al(s) → Al₂O₃(s) + 2 Fe(s) ΔH°rxn = -852 kJ

When 2 moles of Fe are produced, there are released -852kJ.

98.7g of Fe are:

98.7g Fe × (1mol / 55.845g) = 1.767 moles of Fe

If 2 moles of Fe are producen when -852 kJ of energy are involved, 1.767 moles of Fe envolved:

1.767mol × (-852kJ / 2mol Fe) = -753kJ of energy are involved

answer: -

reaction:

na + cl ⇌ nacl

balanced chemical equation:

na + 2cl ⇌ nacl2

sodium + clorine goes to form sodium chloride (table salt).

the product is nacl2.

and the reactants are na and cl.

(note: if you don’t know what ⇌ means, read below: -

⇌(double head arrow) means reversible reaction).