Question

A solution containing 12.0% sodium Hydroxide by mass has a density of 1.131 g/ml . What volume of this solution contains 5.00 mol of NaOH

Answer 1

We can use the formula density =mass/volume

We know that, 100% NaOH=40g

                           12%NaOH=?

100/100 * x = 12/100 *40

x=24/5g

Now , d=1.131;m=24/5g;v=?

  1.131 =24/5/v

1131/1000*5/24=1/v

v=1000/1131*24/5

v=4800/1131

And,

4800/1131 = 1 mol

  ?            =   5 mol

I'll leave the rest to you