Question

8 g NaOH is dissolved in one litre of solution, the
molarity of the solution is:-
(1) 0.2 M
(2) 0.4 M
(3) 0.02 M
(4) 0.8 M​

Answer 1

Explanation:

the correct option is 1 0.2M

Answer 2

$\huge{\mathcal{\boxed{\blue{Solution}}}}$

Given that 8g of Naoh is one litre of solution

first the number of moles of the Naoh is

moles=given mass/molar mass

given mass =8g

molar mass (Naoh)=23+16+1=40u

Moles of the Naoh:

$\large{moles=mass/molar\:mass}$

$\large{moles=8g/40u=0.2mol}$

The molarity of the solution is

➡Molarity = number of moles/volume of solution is litres

$\large{molarity=0.2mol/1litre}$

$\huge{\mathcal{\boxed{\orange{0.2M}}}}$