Question

Question #32650

Answer 1

`"55.5 g"`

Explanation:

Start by calculating the number of moles of calcium chloride that must be dissolved in your solution in order for it to have a molarity of `"0.100 mol L"^(-1)`.

You know that this solution must contain `0.100` moles of calcium chloride for every `"1 L"` of the solution, so you can say that your sample must contain

`5.00 color(red)(cancel(color(black)("L solution"))) * "0.100 moles CaCl"_2/(1color(red)(cancel(color(black)("L solution")))) = "0.500 moles CaCl"_2`

Now, to convert the number of moles of calcium chloride to moles, you need to use the molar mass of the salt.

`0.500 color(red)(cancel(color(black)("moles CaCl"_2))) * "110.98 g"/(1color(red)(cancel(color(black)("mole CaCl"_2)))) = color(darkgreen)(ul(color(black)("55.5 g")))`

The answer is rounded to three sig figs.