1 point
Using the balanced chemical equation; how many moles of ammonia will
be made if 12g of hydrogen gas is reacted with excess nitrogen?
(Remember Hydrogen gas is diatomic) *
N2 + 3 H2 → 2 NH3 (AH = -92.4 kJ. mol-1)
8 moles
6 moles
4 moles
2 moles

4 moles

Explanation:

Step 1: Write the balanced equation

N₂ + 3 H₂ → 2 NH₃ (ΔH = -92.4 kJ.mol⁻¹)

Step 2: Calculate the moles of hydrogen

The molar mass of H₂ is 2.0 g/mol. The moles corresponding to 12 grams are:

Step 3: Calculate the moles of ammonia

The molar ratio of H₂ to NH₃ is 3:2. The moles of ammonia produced from 6.0 moles of hydrogen are:

answer: the enthalpy of the overall chemical reaction is +87.88 kj or +88 kj.

according to hess's law, the overall enthalpy of a reaction is the difference between the sum of enthalpy values of all the products and the sum of enthalpy values of all the reactants.

δh(reaction) = ∑nδh(products) - ∑nδh(reactants)

δh(reaction) = [δh +δh] - [δh]

δh(reaction) = [1(-287.02) + 1(0) ] - [1(-374.9)] kj = +87.88 kj

here, δh (pcl3) = -287.02 kj, δh(cl2) = 0, δh(pcl5) = -374.9 kj

therefore, enthalpy of the overall reaction is +87.88 kj or +88 kj.

not clear