Question

Find molarity of 20% w/w naoh solution. Density of solution is 12 ml

Answer 1

Answer:

60..

Explanation:

M= w/w%× d × 10 / gmwt

w/w%=20, d = 12 ml = 12 cc , gmwt = 40

= 20 ×12 ×10/ 40

= 200×12/40

= 2 ×12

= 60

hope its help u.....TC❤

Answer 2

Answer :

Given -

• The w/w % of the solution = 20%
• Density of the solution of NaOH = 12 g/ml

To Find -

• Molarity ?

Solution -

We are given, w/w % = 20%.

Hence, 20 g of NaOH is in 100 g of solution.

Now, Density = Mass/Volume.

⇒ 12 = 100/Volume

⇒ Volume = 100/12

⇒ Volume = 8.33 mL = 8.33/1000 = 0.00833 L

Molar mass of NaOH = 23 u + 18 u + 1 u = 40 u = 40 g/mol.

Now, Molarity = No. of moles of solute/Volume of solution in litres.

⇒ Molarity = (Total mass/Molar mass)/Volume of solution in L

⇒ Molarity = (20/40)/0.00833

⇒ Molarity = (1/2)/0.00833

⇒ Molarity = 0.5/0.00833

⇒ Molarity = 60 M.