A chemistry student needs 45.00g of 4-methyl-2-pentanone for an experiment. He has available 0.50 kg of a 10.9% w/w solution of 4-methyl-2-pentanone in acetone. Calculate the mass of solution the student should use.

0.412 Kg of Solution

Explanation:

To solve this problem we will first find the number of grams of solute contained by the given amount of solution as,

w/w% = weight of solute / weight of solution * 100

Solving for weight of solute,

Weight of solute = w/w% * weight of solution / 100

Putting values,

Weight of solute = 10.9 * 500 g / 100

Weight of solute = 54.5 g

Hence,

54.5 g of solute was contained by = 500 g of solution

So,

45.0 g of solute will be contained by = X g of solution

Solving for X,

X = 45.0 g * 500 g / 54.5 g

X = 412.84 g

Or,

X = 0.412 Kg of Solution