To measure the protective action of action of different lyophilic sols quantitatively, the gold number was introduced by Zsig-mondy. It is defined as the minimum number of dry protective colloid which much be added to `10ml` of a specially prepared red gold sol just to prevent a change to vlolet (i.ie an incease in particle size) on the addition of `1ml` of `10` precent sodium chloride solution.

Options

A. millimoles
B. grams
C. milligrams
D. moles

Answer

C

Explanation

The weight in milligrams of protective colloid that prevents the coagulation of `10mL` of a given sol on adding `1mL` of a `10%` solution `NaCl` is called gold number.