**Step 1: Moles of aspirin**

molar mass HC _{9}H_{7}O_{4} = 180.1 g/mol

$\mathbf{325}\mathbf{}\overline{)\mathbf{mg}}\left(\frac{{10}^{-3}\overline{)g}}{1\overline{)\mathrm{mg}}}\right)\left(\frac{1\mathrm{mol}}{180.1\overline{)g}}\right)\mathbf{=}$**1.8046x10**^{-3 }**mol**

**Step 2: Molarity of aspirin**

**$\overline{){\mathbf{Molarity}}{\mathbf{}}{\mathbf{=}}{\mathbf{}}\frac{\mathbf{moles}\mathbf{}\mathbf{of}\mathbf{}\mathbf{solute}}{\mathbf{L}\mathbf{}\mathbf{of}\mathbf{}\mathbf{solution}}}\phantom{\rule{0ex}{0ex}}\mathbf{Molarity}\mathbf{}\mathbf{=}\mathbf{}\frac{\mathbf{1}\mathbf{.}\mathbf{8046}\mathbf{\times}{\mathbf{10}}^{\mathbf{-}\mathbf{3}}\mathbf{}\mathbf{mol}}{\mathbf{237}\mathbf{}\overline{)\mathbf{mL}}}\mathbf{\left(}\frac{\mathbf{1}\mathbf{}\overline{)\mathbf{mL}}}{{\mathbf{10}}^{\mathbf{-}\mathbf{3}}\mathbf{}\mathbf{L}}\mathbf{\right)}$**

**Molarity = 7.614x10 ^{-3 }M**

A typical aspirin tablet contains 325 mg acetylsalicylic acid (HC _{9}H_{7}O_{4}). Calculate the pH of a solution that is prepared by dissolving two aspirin tablets in enough water to make one cup (237 mL) of solution. Assume the aspirin tablets are pure acetylsalicylic acid, K_{a} = 3.3 X 10 ^{-4}.

Frequently Asked Questions

What scientific concept do you need to know in order to solve this problem?

Our tutors have indicated that to solve this problem you will need to apply the Weak Acids concept. If you need more Weak Acids practice, you can also practice Weak Acids practice problems.

What professor is this problem relevant for?

Based on our data, we think this problem is relevant for Professor Danna's class at UT.

What textbook is this problem found in?

Our data indicates that this problem or a close variation was asked in Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition. You can also practice Chemistry: An Atoms First Approach - Zumdahl Atoms 1st 2nd Edition practice problems.