Question

What is the molarity of a solution that contains 30g of naoh in 500ml of solution?

Answer 1

Answer: 1.5 M.

Explanation: Gram formula mass of NaOH= 23g+16g+1g=40g

30g sample= 0.75 mole.

0.75mol/0.500L=1.5 M

Answer 2

Given: A solution contains 30g of NaOH in 500ml of solution.

To find: We have to find the molarity.

Solution:

The molarity of a solution is given as-

$m = \frac{n}{v} \times 1000$

Where n is the number of moles of v is the volume of the solution.

The molecular mass of NaOH is 23+16+1=40grams.

Thus the number of moles will be-

$\frac{30}{40} = \frac{3}{4}$

The volume of the solution is 500ml.

Putting the value in the above formula we get-

$m = \frac{ \frac{3}{4} }{500} \times 1000 \\ m = \frac{3}{4} \times 2 \\ m = 1.5$

The molarity of the solution is 1.5mol/L.