Question

The molarity of sodium hydroxide solution by dissolving 4 gram of it in 250ml aqueous solution?

Answer 1

Given

• Mass of NaOH = 4 gram.

• Volume of the solution = 250 ml

To Find

Molarity of the solution

Formula

Molarity =

$\frac{no \: of \: moles \: of \: solute}{volume \: of \: solution}$

Calculations

We know, Molar mass of NaOH = 40 gram.

Hence, number of moles of NaOH in its 4 gram solution = 4/40 = 0.1 gram

Using formula of molarity ( Volume = 250 ml = 0.250 l )

Molarity =

$\frac{0.1}{0.250} = 0.4$

Hence, molarity of the solution is 0.4 M.