Question

Choose the thermochemical equation that illustrates ΔH°f for Li2SO4. Choose the thermochemical equation that illustrates ΔH°f for Li2SO4. 8 Li2SO4(s) → 16 Li(s) + S8(s, rhombic) + 16 O2(g) Li2SO4(aq) → 2 Li+(aq) + SO42-(aq) 2 Li+(aq) + SO42-(aq) → Li2SO4(aq) 16 Li(s) + S8(s, rhombic) + 16 O2(g) → 8 Li2SO4(s) 2 Li(s) + 1/8 S8(s, rhombic) + 2 O2(g) → Li2SO4(s)

Answer 1

Answer:

2Li(s) + ⅛S₈(s, rhombic) + 2O₂(g) → Li₂SO₄(s)  

Explanation:

A thermochemical equation must show the formation of 1 mol of a substance from its elements in their most stable state,.

The only equation that meets those conditions is the last one.

A and B are wrong , because they show Li₂SO₄ as a reactant, not a product.

C is wrong because Li⁺ and SO₄²⁻ are not elements.

D is wrong because it shows the formation of 8 mol of Li₂SO₄.