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hjlf
3 years ago
14

How much heat is absorbed/released when 20.00 g of NH3(g) (17.0307g/mol) react in the presence of excess O2(g) to produce NO(g)

and H2O(l) according to the following chemical equation? 4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(l) ΔH° = 1168 kJ
Chemistry
1 answer:
irina1246 [14]3 years ago
8 0

Answer:

342.8 kJ are absorbed

Explanation:

In the reaction:

4 NH3(g) + 5 O2(g) → 4 NO(g) + 6 H2O(l) ΔH° = 1168 kJ

<em>As ΔH > 0, the heat is absorbed. Also, when 4 moles of NH3 are involved in the reaction, there are absorbed 1168 kJ</em>.

Having this in mind, moles of NH3 in 20.00g are:

20.00g × (1mol / 17.0307g) = <em>1.174 moles</em>

<em></em>

Thus, 1.174 moles of NH3 absorbed:

1.174 moles × (1168 kJ / 4 moles) = <em>342.8 kJ are absorbed</em>.

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