# How many grams of fructose (#C_6H_12O_6#) must be dissolved in 882g of 12 acetic acid to raise the boiling point by 7.4°C? The boiling point constant for acetic acid is 3.08 °C/m?

##### 1 Answer

You must add 380 g of fructose.

#### Explanation:

The formula for boiling point elevation is

#color(blue)(bar(ul(|color(white)(a/a)ΔT_"b" = iK_"b"mcolor(white)(a/a)|)))" "#

where

#i# is the van't Hoff factor#ΔT_"b"# is the boiling point elevation#K_"b"# is the boiling point elevation constant#m# is the molality of the solution

We can solve the equation for the molality of the solution.

#m = (ΔT_"b")/(iK_"b")#

In this problem,

∴

Next, we calculate the moles of fructose.

The formula for molality is

#color(blue)(bar(ul(|color(white)(a/a) "Molality" = "moles of solute"/"kilograms of solvent"color(white)(a/a)|)))" "#

∴

Finally, convert moles of fructose to grams of fructose.