Question

0.25g of lyophilic colloid is added to 100ml of gold solution to prevent the coagulation on adding 1 ml 10% Nacl solution. what will be the gold number of lyophilic colloid?

Answer 1

Hey mate,

◆ Gold Number-
It's the minimum amount of protective colloid in milligrams which prevents a colour change from red to violet of 10ml gold sol by the addition of 1 ml of 10%NaCl solution.

◆ Answer- 25

◆ Explanation-
# Given-
0.25 mg of colloid is added to 100 ml gold solution.

# Solution-
For 10 ml gold solution, colloid required is calculated by
x = 0.25 × 10 / 100
x = 0.025 g
x = 25 mg.

Thus gold number of given lyophillic colloid will be 25.

Hope that is helpful..