MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Uses of Hydrogen

The gold numb...

Question

The gold number of certain lyophillic colloids is given below. Which of the following is most effective in protection of lyophobic colloids against coagulation?
Gelatine – 0.01, Haemoglobin – 0.07, Albumen – 0.2, Potato starch – 25

A

Gelatine

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

B

Haemoglobin

No worries! We‘ve got your back. Try BYJU‘S free classes today!

C

Albumen

No worries! We‘ve got your back. Try BYJU‘S free classes today!

D

Potato starch

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is A Gelatine
Lower the gold number, more effective is its protective action.

Suggest Corrections

thumbs-up

3

Similar questions

Q. Lyophilic colloidal sols are much more stable than lyophobic colloidal sols. This is due to the extensive solvation of lyophilic colloidal sols, which form a protective layer outside it which prevents it from forming associated colloids. Lyophilic colloidal sols also protect lyophobic colloidal sols from precipitation by the action of electrolytes. This is due to the formation of a protective layer by the lyophilic sols outside lyophobic sols. Lyophilic sols are also called protective sols.
Gelatin (lyophilic) protects gold sol (lyophobic) from coagulation on the addition of a solution of sodium chloride. The protective powers of different colloidal sols are measured in terms of gold number.
Gold number is defined as the amount of protective sol in milligrams that prevents the coagulation of 10 mL of a given gold sol on adding 1 mL of a

10 %

solution of sodium chloride. Thus, the smaller the gold number of a lyophilic sol, the greater is the protective power.

The coagulation of 100 mL of colloidal solution of gold is completely prevented by the addition of 0.25 g of a substance “

X

” to it before the addition of 1 mL of

10 % N a C l

solution. The gold number of “

X

Q. Assertion :Lyophilic colloids such as starch, gelatin etc., act as protective colloids. Reason: Protective power of lyophilic colloids is expressed in terms of gold number.

Q. Gold numbers of some colloids are :

0.005 - 0.01

0.15 - 0.25

0.04 - 1.0

15 - 25

Which among these is a better protective colloid?

The protective power of the lyophilic colloids is expressed in terms of gold number a term introduced by Zsigmondy. Gold number is the number of milligrams of the protective colloid which prevent the coagulation of

10

ml of red gold sol. When

1

10

percent solution of sodium chloride is added to it. Thus, smaller the gold number of lyophilic colloid, the greater is the protective power.

On addition of one mL of solution of

10 %

N a C l

10

mL of red gold sol in presence of

0.025

g of starch, the coagulation is just prevented. The gold number of starch is :

Q. Assertion :Lyophilic colloids have a unique property of protecting lyophobic colloids. Reason: Lyophilic colloids are extensively solvated.

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Dihydrogen - Preparation Methods; Physical and Chemical Properties; Uses

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Uses of Hydrogen

Standard XII Chemistry

Join BYJU'S Learning Program

CrossIcon