Question 4f6f6

Dec 5, 2017

$\text{1.65 g}$

Explanation:

The first thing that you can calculate here is the number of moles of calcium chloride dissolved to make your solution.

As you know, the molarity of the solution tells you the number of moles of solute present in every $\text{1 L} = {10}^{3}$ $\text{mL}$ of the solution.

In your case, a $\text{0.550-M}$ solution will contain $0.550$ moles of calcium chloride, the solute, in every ${10}^{3}$ $\text{mL}$. This means that your sample will contain

27.0 color(red)(cancel(color(black)("mL solution"))) * "0.500 moles CaCl"_2/(10^3color(red)(cancel(color(black)("mL solution")))) = "0.01485 moles CaCl"_2#

To convert the number of moles to grams, you need to use the molar mass of the solute.

$0.01485 \textcolor{red}{\cancel{\textcolor{b l a c k}{\text{moles CaCl"_2))) * "110.98 g"/(1color(red)(cancel(color(black)("mole CaCl"_2)))) = color(darkgreen)(ul(color(black)("1.65 g}}}}$

The answer is rounded to three sig figs.