To determine the mass (or weight) by volume percentage concentration of a solution, follow these steps:
1. Identify the mass of the solute and the volume of the solution:
- The mass of NH4Cl (solute) is 37.0 grams.
- The volume of the solution is 180.0 milliliters.
2. Use the formula for mass by volume percentage concentration:
[tex]\[
\text{Concentration} \, (\%) = \left( \frac{\text{mass of solute (g)}}{\text{volume of solution (mL)}} \right) \times 100
\][/tex]
3. Substitute the given values into the formula:
[tex]\[
\text{Concentration} \, (\%) = \left( \frac{37.0 \, \text{g}}{180.0 \, \text{mL}} \right) \times 100
\][/tex]
4. Calculate the concentration:
[tex]\[
\text{Concentration} \, (\%) = 20.555555555555554
\][/tex]
5. Round the result to reflect the correct number of significant figures:
- The mass of NH4Cl (37.0 g) has 3 significant figures.
- The volume of the solution (180.0 mL) has 4 significant figures.
- The final answer should have the smallest number of significant figures from the given data, which is 3.
So, the rounded concentration is:
[tex]\[
20.6
\][/tex]
Therefore, the mass by volume percentage concentration of the NH4Cl solution is 20.6%.
