# Problem: Use bond energies to calculate ΔHrxn for the reaction: N2(g) + 3H2(g) → 2NH3(g)Average Bond EnergiesBondBond Energy(kJ/mol)N≡N946H-H436N-H389

###### FREE Expert Solution
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###### FREE Expert Solution

We are asked to use bond energies to calculate ΔHrxn for the reaction: N2(g) + 3 H2(g) → 2 NH3(g).

To calculate the ΔH°rxn using bond energies, we’re going to use the following equation:

Let’s first figure out what kind of bonds and how many moles are present in each reactants and products by drawing the Lewis structure because the given bond energies are per mole.

Balanced Reaction:  N2(g) + 3 H2(g)→ 3 H2(g) + 2 NH3(g)

*always make sure that the given reaction is balanced

Therefore, we need to do the following first:

Step 1: Determine the central atom in this molecule.

Step 2: Calculate the total number of valence electrons present.

Step 3: Draw the Lewis structure for the molecule.

Reactants:

N2:

81% (244 ratings)
###### Problem Details

Use bond energies to calculate ΔHrxn for the reaction: N2(g) + 3H2(g) → 2NH3(g)

Average Bond Energies

 Bond Bond Energy(kJ/mol) N≡N 946 H-H 436 N-H 389

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Bond Energy concept. If you need more Bond Energy practice, you can also practice Bond Energy practice problems.

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Based on our data, we think this problem is relevant for Professor Gorun's class at SHU.