Question

Consider the following data.

Mg(s) + S(s) <— —> MgS(s). TriangleH=-598.0 kJ

SO2(g) <— —> S(s) + O2(g) TriangleH= +296.8 kJ

3 Mg(s) + SO2(g) <— —> MgS(s) + 2 MgO(s) TriangleH = -1504.6 kJ

Use Hess’s law to calculate TriangleH for the reaction below.

2 Mg(s) + O2(g) <— —> 2 MgO(s)

1) TriangleH = ____ kJ

Answer 1

-598+296.8--1504.6

= 1203.4kJ