Question

a solution having density 1.6gm/ml is 67% by weight calculate its percentage if it diluted to density 1.2g/ml​

Answer 1

Answer:

A solution of a specific gravity 1.6 g mL

−1

is 67% by mass. The % by mass of the solution of the same acid, if it is diluted to the specific gravity 1.2 g mL

−1

is (as nearest integer) :

December 20, 2019avatar

Sudheeksha Prakashini

SHARE

ANSWER

Assume 100 mL of solution of 67% by mass of specific gravity 1.6 gmL

−1

.

Mass of solution =100×1.6=160g.

Mass of solute =

100

67×160

=107.2g.

Now, consider XgH

2

O is added to it.

Mass of new solution =(160+X)g ...(i)

Also, XgH

2

O means X mL of H

2

O and, thus,

Volume of new solution = (100+X)

Using specific gravity of the solution, the mass of new solution

=(100+X)×1.2=(120+1.2X)g ...(ii)

By Eqs. (i) and (ii), we get

160+X=120+1.2X

X =200 mL or 200 g

% by mass of new solution

=

160+200

107.2

×100=29.78%.

So, the answer is 30.