Question

current attempt in progress
for the following equation which of the statements listed below is true?
n₂(g) + 3h₂(g) → 2nh₃(g) + 91.8 kj

the reaction is a decomposition.
the reaction involves an acid.
2 molecules of nh₃ are produced.
an insoluble precipitate forms during the reaction.
the reaction is endothermic.

Explanation:

• Decomposition reaction: A decomposition reaction is when a single compound breaks down into two or more simpler substances. Here, \(N_2\) and \(H_2\) combine to form \(NH_3\), so it is not a decomposition reaction.
• Involving an acid: There are no acid - related species (\(H^+\) donor in the Arrhenius sense or \(H^+\) acceptor in the Bronsted - Lowry sense) in the reaction \(N_2(g)+3H_2(g)\to2NH_3(g)+91.8\ kJ\).
• Molecules of \(NH_3\): According to the stoichiometry of the balanced chemical equation \(N_2(g)+3H_2(g)\to2NH_3(g)+91.8\ kJ\), when the reaction occurs as written (based on mole ratios in the equation), 2 moles of \(NH_3\) are produced. In terms of molecules, using Avogadro's number \(N = n\times N_A\) (\(n = 2\ mol\) and \(N_A=6.022\times 10^{23}\ mol^{-1}\)), \(2\times6.022\times 10^{23}\) molecules of \(NH_3\) are produced.
• Insoluble precipitate: All the species \(N_2\), \(H_2\), and \(NH_3\) are gases. There is no formation of a solid (precipitate) in the reaction.
• Endothermic or exothermic: An exothermic reaction releases heat (\(\Delta H<0\)), and an endothermic reaction absorbs heat (\(\Delta H > 0\)). Since \(91.8\ kJ\) of energy is released (written on the product side), the reaction is exothermic.

Answer:

2 molecules of \(NH_3\) are produced.