Given the standard enthalpy changes for the following two reactions: (1) 2Zn(s) + O2(g)2ZnO(s)...... ΔH° = -696.6 kJ (2) Zn(s) + Cl2(g)ZnCl2(s)......ΔH° = -415.0 kJ

Question

Given the standard enthalpy changes for the following two reactions:

(1) 2Zn(s) + O₂(g)2ZnO(s)...... ΔH° = -696.6 kJ

(2) Zn(s) + Cl₂(g)ZnCl₂(s)......ΔH° = -415.0 kJ

what is the standard enthalpy change for the reaction:

(3) 2ZnCl₂(s) + O₂(g)2ZnO(s) + 2Cl₂(g)......ΔH° = ?

_____kJ

Answer 1

2Zn + O₂ —-> 2ZNO H= -696.6 KJ

2ZnCl₂ —-> 2Zn + 2Cl_2. H= -(-415.0) (2) KJ

2ZnCl₂ + O₂ —-> 2ZnO + 2Cl₂ H= 133.4 KJ