# Question ad51c

Aug 14, 2017

%"mass glucose" = 17.4%

#### Explanation:

We're asked to find the percent by mass of glucose, given how much is dissolved in a known amount of water.

The formula for mass percentage of a substance $x$ is given by

$\underline{\overline{| \stackrel{\text{ ")(" "%"mass"color(white)(l)x = ("mass of"color(white)(l)x)/("total mass") xx 100%" }}{|}}}$

(Here, $x$ represents glucose.)

The total mass of the solution is the mass of the *glucose plus the mass of *water:

$\text{total mass" = overbrace(156color(white)(l)"g")^"glucose" + overbrace(740color(white)(l)"g")^"water" = color(red)(ul(896color(white)(l)"g}$

The mass percentage of glucose is therefore

color(blue)(%color(white)(l)"mass glucose") = (156color(white)(l)"g glucose")/(color(red)(896color(white)(l)"g solution")) xx 100% = color(blue)(ulbar(|stackrel(" ")(" "17.4%" ")|)#