Question

4. Liquid A has a refractive index of 1.415 and liquid B has a refractive index of 1.524. A solution

is prepared by mixing liquid A with liquid B. If the refractive index of the resulting solution is

1.457, does the solution have more of liquid A or more of liquid B? What is the % Liquid A in

the mixture?

Answer 1

Solution :-

Refractive index of A= 1.415

Refractive index of B =1.524

Refractive index of mixture = 1.457

The mixture has refractive index 1.457 which is close to the value of solution A therefore mixture will have more of liquid A.

Lets assume fraction of the liquid A= x

Then fraction of liquid B = (1-x)

Using this we can find the fraction of A in the mixture

(x*1.415)+((1-x)*1.524) =1.457

1.415x + 1.524 -1.524x = 1.457

1.415x – 1.524x = 1.457-1.524

-0.109 x = -0.067

X = -0.067/-0.109

X = 0.615

Therefore fraction of A in the mixture is 0.615

Lets convert the fraction to the percent

% A = 0.615 * 100 %

      = 61.5 %

Therefore the mixture have 61.5 % of liquid A