Hess's Law
8. Thermochemistry / Hess's Law / Problem 3
Select the correct addition of (i) and (ii) to get (iii)
(i) POCl3 + Cl2 → PCl5 + 1/2 O2
(ii) PCl3 + Cl2 → PCl5
(iii) 2 POCl3 → 2 PCl3 + O2
a.
POCl3 + Cl2 → PCl5 + 1/2 O2
PCl3 + 1/2 O2 → POCl3 ________________________
PCl3 + Cl2 → PCl5
b.
POCl3 + Cl2 → PCl5 + 1/2 O2
PCl5 → PCl3 + Cl2________________________
POCl3 → PCl3 + 1/2 O2
c.
2 [ POCl3 + Cl2 → PCl5 + O2 ]
2 [ PCl3 + O2 → 2 POCl3 ]________________________
2 POCl3 → 2 PCl3 + O2
d.
2 [ POCl3 + Cl2 → PCl5 + 1/2 O2 ]
2 [ PCl5 → PCl3 + Cl2 ]________________________
2 POCl3 → 2 PCl3 + O2
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