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Calculating Delta H

Use some or all of the following reaction enthalpies to calculate delta H for the reaction:

3NH3(aq) + ClO- (aq) --> N2H4(g) + NH4+ (aq) + Cl- (aq) + OH- (aq)

Cl- (aq) + H2O2(l) --> H2O(l) + ClO- (aq) delta H = - 6.5kJ/mol
N2(g) + 3H2(g)--> 2NH3(g) delta H = -160.6kJ/mol
H2O(l) + 1/2 N2H4(g) --> 1/2 H2O2(l) + NH3(aq) delta H = + 63.9kJ/mol
3H2(g) + 2 ClO2- (aq) --> ClO- (aq) + Cl- (aq) + 3H2O(l) delta H = - 424.9 kJ/mol
NH3 (aq) + H2O (l) --> NH4+ (aq) + OH- (aq) delta H = + 3.6 kJ/mol

Use the standard enthalpies of formation to calculate delta H for the reaction of ammonia and hypochlorite shown above: delta H formation (NH3(aq)) = - 80.3 kJ/mol; delta H formation (ClO-(aq) = -75.7 kJ/mol; delta H formation (N2H4(g)) = +95.4 kJ/mol; delta H formation (NH4+(aq)) = - 132.5 kJ/mol; delta H formation (Cl-(aq) = - 167.2 kJ/mol; delta H formation (OH-(aq)) = -230.0 kJ/mol

Solution Preview

Hi there,

Here is my explanation:
In order to obtain the reaction above, we need to have the following operation:

H2O+ClO- ...

Solution Summary

The expert calculates delta H reaction enthalpies.

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