Question

A solution of an unknown compound has a concentration of 11.7 % by mass. Howmany moles are present in 2.780 kg of solution if the solute has a molar mass of118.5 g/mol?

Answer 1

We are required to calculate the number of moles.

Given:

concentration = 11.7%

molar mass = 118.5 g/mol

mass = 2.780 kg = 2780 g

To calculate the number of moles we can use the following equation:

`n\text{ =}(m)/(M)`

Where m is the mass and M is the molar mass of the unknown solution.

n = 2780 g /118.5 g/mol

n = 23.46 moles