Question

what do you mean by a gold number

Answer 1

HEYAA!!
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ANSWER IS.
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GOLD NUMBER  is defined as 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 2

HEY MATE HERE IS YOUR ANSWER:-

GOLD NUMBER:-
The number of milligrams of the protective colloid required to just prevent the coagulation of a given gold Solution when 1 ml of a 10% solution chloride is. added to it .

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