# Question 85f01

Nov 5, 2017

$\text{1.75 moles}$

#### Explanation:

The idea here is that we use molarity to show the number of moles of solute present in exactly $\text{1 L} = {10}^{3}$ $\text{mL}$ of a given solution.

In your case, a calcium chloride solution is said to have a molarity of $\text{3.50 M}$. This tells you that every $\text{1 L}$ of this solution contains exactly $3.50$ moles of calcium chloride, the solute.

Since you know that

$\text{1 L} = {10}^{3}$ $\text{mL}$

you can say that this solution contains $3.50$ moles of solute for every ${10}^{3}$ "mL" of the solution.

Your sample has a volume of

"500.0 mL" = (10^3color(white)(.)"mL")/color(blue)(2)

which means that it will contain

"3.50 moles CaCl"_2/color(blue)(2) = color(darkgreen)(ul(color(black)("1.75 moles CaCl"_2)))

The answer is rounded to three sig figs, the number of sig figs you have for the molarity of the solution.