Question

‘w g’ sodium hydroxide is dissolved in sufficient water to get ‘V mL’ of solution of density ‘d kg/m3

.

The molar ratio of water and sodium hydroxide in the solution is

(A) 40 (Vd – w) : 18 w (B) 18 w : 40 (Vd – w) (C) 40 Vd : 18 w (D) 40 w : 18 (Vd – w)​

Answer 1

Answer:

(B) 18 w : 40 (Vd – w)

Explanation:

one moles of sodium hydroxide = 40 gm of sodium hydroxide. so we can said ; if want prepare 1 molar NaOH solution then we need 40 gm NaOH dissolve in one liter of water so it became one 1 molar NaOH solution.

Answer 2

Answer:

1M

The molar mass of NaOH is 40 g/mol.

The number of moles of NaOH is equal to the ratio of its mass to molar mass.

The number of moles of NaOH =

40g/mol

40g -ans

=1mol

The molarity of NaOH solution is the ratio of number of moles of NaOH to total volume of solution in L.

M=

1L

1mol

=1M