To calculate the mass percent of aspirin (C₉H₈O₄) in acetonitrile (CH₃CN) when 6.5 g of aspirin is dissolved in 450 g of acetonitrile, follow these steps:
1. Determine the Total Mass of the Solution:
Add the mass of the aspirin to the mass of the acetonitrile to get the total mass of the solution.
- Mass of aspirin = 6.5 g
- Mass of acetonitrile = 450 g
- Total mass of the solution = 6.5 g + 450 g = 456.5 g
2. Calculate the Mass Percent of Aspirin:
The mass percent of a component in a solution is given by the formula:
[tex]\[
\text{Mass percent} = \left( \frac{\text{mass of component}}{\text{total mass of solution}} \right) \times 100
\][/tex]
Using the given values:
[tex]\[
\text{Mass percent of aspirin} = \left( \frac{6.5 \, \text{g}}{456.5 \, \text{g}} \right) \times 100
\][/tex]
3. Perform the Division:
Divide the mass of the aspirin by the total mass of the solution:
[tex]\[
\frac{6.5}{456.5} \approx 0.014238773
\][/tex]
4. Multiply by 100 to Get the Mass Percent:
Multiply the result by 100 to convert it to a percentage:
[tex]\[
0.014238773 \times 100 \approx 1.4238773274917853
\][/tex]
Therefore, the mass percent of aspirin in the acetonitrile solution is approximately 1.42%.
