Question

A solution is made by dissolving 45.0 g of CaCl2 in enough water to form exactly 3 liters of solution. What is the molarity of the solution? Answer choices: 37 M 45 M 15.0 M .135 M

Answer 1

0.135M

Explanations:

The formula for calculating the molarity of a solution is expressed as

`molarity=\frac{moles\text{ of solute}}{volume\text{ of solution}}`

Determine the moles of CaCl2

`\begin{gathered} mole\text{ of CaCl}_2=\frac{mass}{molar\text{ mass}} \\ mole\text{ of CaCl}_2=(45.0g)/(110.98) \\ mole\text{ of CaCl}_2=0.4055moles \end{gathered}`

Determine the molarity of the solution

`\begin{gathered} molarity=(0.4055)/(3) \\ molarity=0.135M \end{gathered}`

Hence the molarity of the solution is 0.135M