Question #c814d

1 Answer
Apr 6, 2016

Answer:

#"3.5% m/v"#

Explanation:

I'm assuming that the problem wants you to find the mass by volume percent concentration, #"% m/v"#, for this calcium chloride solution.

A solution's mass by volume percent concentration tells you how many grams of solute, which in your case is calcium chloride, #"CaCl"_2#, are present in #"100 mL"# of solution.

This means that in order to find a solution's #"% m/v"# concentration, you essentially have to determine how many grams of solute you get in #"100 mL"# of said solution.

In your case, you know that #"250 mL"# of this solution contain #"8.56 g"# of calcium chloride, which means that #"100 mL""# will contain

#100 color(red)(cancel(color(black)("mL"))) * "8.56 g CaCl"_2/(250color(red)(cancel(color(black)("mL")))) = "3.46 g CaCl"_2#

So, if this is how much solute you get per #"100 mL"# of solute, you can say that the solution's #"%m/v"# concentration is equal to

#"% m/v" = color(green)(|bar(ul(color(white)(a/a)"3.5% CaCl"_2color(white)(a/a)|))) -># rounded to two sig figs