Question

The energy diagram shown represents the chemical reaction between solid ammonium chloride and solid barium hydroxide octahydrate:2NH4Cl(s)+Ba(OH)2⋅8H2O(s)→2NH3(aq)+BaCl2(aq)+10H2O(l)The ΔH for this reaction is 54.8 kJ . How much energy would be absorbed if 27.1 g of NH4Cl reacts?Express your answer with the appropriate units.Answer= (value)/(units)

Answer 1

According to the chemical equation, the reaction absorbs 54.8 kJ per 2 moles of NH4Cl because that's the stoichiometry coefficient of this molecule.

Now, we need to find the number of moles in each mole of NH4Cl.

`\begin{gathered} N=14.0067 \\ H_4=4\cdot(1.00784)=4.03136 \\ Cl=35.453 \end{gathered}`

Then, we add them to find the molar mass.

`NH_4Cl=53.49\cdot\frac{g}{\text{mol}}`

This means that 1 mole of NH4Cl equals 53.49 grams.

At last, we multiply the mass of NH4Cl (27.1 g) by two ratios, the first ratio is about the molar mass, and the second ratio is about the amount of heat per moles.

`27.1g\cdot\frac{1\text{mol}}{53.49g}\cdot\frac{54.8kJ}{2\text{mol}}=(1485.08)/(106.98)kJ=13.88kJ`

Therefore, the amount of energy that would be absorbed is 13.88 kJ.