# Question #97eda

##### 1 Answer

#### Explanation:

Your goal here is to figure out the number of grams of sodium chloride, your solute, present in

Since you know that your sample contains **mass of the solution** is equal to

#overbrace("0.5 g")^(color(blue)("mass of solute")) + overbrace("20 g")^(color(blue)("mass of solvent")) = overbrace("20.5 g")^(color(blue)("mass of solution"))#

Now, you know that you have

#100 color(red)(cancel(color(black)("g solution"))) * overbrace("0.5 g NaCl"/(20.5color(red)(cancel(color(black)("g solution")))))^(color(blue)("known composition")) = "2.439 g NaCl"#

Since a solution's **percent concentration by mass**, *for every* *of solution*, you can say that your solution will be

#color(darkgreen)(ul(color(black)("% by mass = 2% NaCl")))#

The answer must be rounded to one **significant figure**, the number of sig figs you have for your values.