Question

A flask contains 85.5 g `C_12H_22O_11` (sucrose) in 1.00 liters of solution. What is the molarity?

Answer 1

`"molarity" = 0.250M`

Explanation:

We're asked to find the molar concentration (molarity) of a sucrose solution, given the volume of solution and mass of solute.

The equation for molarity is

`"molarity" = "mol solute"/"L soln"`

We're given the volume is `1.00` `"L"`, so we just need to find the moles of solute (we're given grams) via the molar mass of sucrose (`342.30` `"g/mol"`):

`85.5cancel("g sucrose")((1color(white)(l)"mol sucrose")/(342.30cancel("g sucrose"))) = color(red)(0.250` `color(red)("mol sucrose"`

Therefore, we have

`"molarity" = (color(red)(0.250color(white)(l)"mol sucrose"))/(1.00color(white)(l)"L soln") = color(blue)(0.250M`