Calculate the mass percentage of aspirin \((C_9H_8O_4 )\) in acetonitrile \((CH_3CN)\) when 6.5 g of \(C_9H_8O_4\) is dissolved in 450 g of \(CH_3CN.\)
Solution and Explanation
Then, total mass of the solution = (6.5+ 450) g
= 456.5 g
Therefore, mass percentage of \(C_9H_8O_4 = (\frac{6.5}{456.5}) \times100%\)
\(= 1.424\%\)
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Concepts Used:
Concentration of Solutions
It is the amount of solute present in one liter of solution.
Concentration in Parts Per Million - The parts of a component per million parts (106) of the solution.
Mass Percentage - When the concentration is expressed as the percent of one component in the solution by mass it is called mass percentage (w/w).
Volume Percentage - Sometimes we express the concentration as a percent of one component in the solution by volume, it is then called as volume percentage
Mass by Volume Percentage - It is defined as the mass of a solute dissolved per 100mL of the solution.
Molarity - One of the most commonly used methods for expressing the concentrations is molarity. It is the number of moles of solute dissolved in one litre of a solution.
Molality - Molality represents the concentration regarding moles of solute and the mass of solvent.
Normality - It is the number of gram equivalents of solute present in one liter of the solution and it is denoted by N.
Formality - It is the number of gram formula present in one litre of solution.