How many grams of [tex][tex]$AgBr$[/tex][/tex] would be required to produce [tex][tex]$75.0 \, \text{g} \, NaBr$[/tex][/tex]?

[tex]\[
\begin{array}{c}
2 \, \text{AgBr} + \text{Na}_2\text{S}_2\text{O}_3 \rightarrow \text{Ag}_2\text{S}_2\text{O}_3 + 2 \, \text{NaBr} \\
\text{AgBr}: 187.77 \, \text{g/mol} \\
\text{NaBr}: 75.0 \, \text{g} \\
\end{array}
\][/tex]

Calculate the mass of [tex][tex]$AgBr$[/tex][/tex] (g).



Answer :

Sure, let's work through this problem step-by-step.

1. Identify the molar masses of the compounds involved:
- Molar mass of AgBr (Silver Bromide) is given as 187.77 g/mol.
- Molar mass of NaBr (Sodium Bromide) is given as 102.89 g/mol.

2. Calculate the moles of NaBr produced:
- We start with 75.0 grams of NaBr.
- To find the number of moles of NaBr, we use the formula:
[tex]\[ \text{moles of NaBr} = \frac{\text{mass of NaBr}}{\text{molar mass of NaBr}} = \frac{75.0 \text{ g}}{102.89 \text{ g/mol}} \approx 0.7289 \text{ moles} \][/tex]

3. Determine the moles of AgBr required:
- From the balanced chemical equation, the stoichiometry between AgBr and NaBr is 1:1. Therefore, the number of moles of AgBr required is the same as the number of moles of NaBr produced.
- Hence, the moles of AgBr required is also approximately 0.7289 moles.

4. Calculate the mass of AgBr required:
- To find the mass of AgBr, we use the formula:
[tex]\[ \text{mass of AgBr} = \text{moles of AgBr} \times \text{molar mass of AgBr} = 0.7289 \text{ moles} \times 187.77 \text{ g/mol} \approx 136.87 \text{ g} \][/tex]

Therefore, approximately 136.87 grams of AgBr would be required to produce 75.0 grams of NaBr.