Question

Addition of 1ml solution of 10%NaCl to 10,ml of gold sol in the presence of 0.025g of starch the coagulation is just prevented the gold number is

Answer 1

Gold Number definition:

Gold Number is a term used in colloidal chemistry. It is defined as the minimum amount of protective colloid in milligrams which prevents a color change from red to violet of 10ml gold sol by the addition of 1 ml of 10%NaCl solution.