Question

400 ml of standard solution is just prevented from coagulation by the addition of 0.96 g of starch before adding 1ml of 10 % Nacl solution. The gold number will be

Answer 1

The answer is 2.4

Refer attachment!!!

Answer 2

Answer:

The gold number of the starch will be equal to 24.

Explanation:

• Gold number: The minimum amount of protective colloids in milligrams required to prevent the coagulation of 10ml of given gold solution when 1ml of 10% of NaCl solution is added to it.

Amount of starch added to 400ml of gold solution required to prevent the coagulation of 1ml of 10% of NaCl solution $=0.96g=960mg$

The starch required to be added to 10ml $=(\frac{960}{400} )*(10)=24$

Therefore gold number of starch is 24.