# If 17.8 grams of KOH dissolve in enough water to make a 198-gram solution, what is the concentration in percent by mass?

May 25, 2016

The concentration of $\text{KOH}$ is 8.99 % by mass.

#### Explanation:

The formula to use is

color(blue)(|bar(ul(color(white)(a/a) "% by mass" = "mass of component"/"total mass of sample" × 100 %color(white)(a/a)|)))" "

"% by mass" = (17.8 color(red)(cancel(color(black)("g"))))/(198 color(red)(cancel(color(black)("g")))) × 100 % = 8.99 %