# Question #82823

##### 1 Answer

#### Explanation:

A solution's **percent concentration by mass**, *mass percent*, tells you how many grams of solute you get for every **solution**.

This means that in order to find a solution's mass percent, all you have to do is figure out how many grams of solute you have in

In your case, you know that you're adding

The first thing to do is figure out the **mass of the solution** by adding the mass of the solute and the mass of the solvent

#m_"solution" = m_"solute" + m_"solvent"#

#m_"solution" = "8.0 g" + "50.0 g" = "58.0 g"#

So, you know that you have *conversion factor* to find the mass of solute that would correspond to

#100 color(red)(cancel(color(black)("g solution"))) * "8.0 g NaOH"/(58color(red)(cancel(color(black)("g solution")))) = "13.8 g"#

Your solution will contain **for every** **of solution**, which means that its mass percent of sodium hydroxide will be

#"% m/m" = color(green)(|bar(ul(color(white)(a/a)color(black)("14 % NaOH")color(white)(a/a)|)))#

The answer must be rounded to two **sig figs**, the number of sig figs you have for the mass of sodium hydroxide.