# Question #ad51c

##### 1 Answer

#### 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

#ulbar(|stackrel(" ")(" "%"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**:

#"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%" ")|)#