Question

4g of NaOH are dissolved in 200 cm3 of water. Find the molarity of the solution

Answer 1

Answer:

moles of soulte = 4 ÷ 40 = 0.1 mol

volume =200 ml

molarity = 0.1 ×1000

200

= 0.5 molar

Answer 2

Solution:

Mass of Naoh dissolved = 4g

Molecular mass of Naoh =23+16+1

=40

Mass of Naoh dissolved.

=4/40

=0.1

volume of water taken

= 200cm³

= 200× 10³ L

The molarity of the solution

=No. of moles Naoh / volumes in litre

=0.1/ 200× 10³

= 0.5 molL¹

Hence the given solution is 0.5M.