Question

In 90 g of 20% (w/w) aqueous salt solution 10 g more water is added. Calculate the final concentration (w/w%) of the solution.

Answer 1

Answer:

initially:20= 90 / 90 + x × 100

20/100=90/90+x

90+x=5(90)

90+x=450

x=450-90

x=360 gm water

......now more 10 gm water is added so

360+10= 370gm

..(w/W)%= 90/370+90 ×100

=90/460×100

=900/46= 19.56%...plz comment if u liked answer

Answer 2

Given:

The mass of solution = 90 gm

The w/w % of aqueous salt solution = 20 %

The mass of water added = 10 gm

To Find:

The final concentration of the solution.

Calculation:

- The mass of salt in the given solution, w = 90 × (20/100) = 18 gm

- After adding water, the final mass of the given solution = 90 + 10 = 100 gm

- The final mass % of the solution = (18/100) × 100

⇒ w/w % = 18 %

- So, the final concentration of the solution is 18 % (w/w).