Download App

Is Matter Around Us Pure — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceIs Matter Around Us Pure1 Mark
Question
Write one property of colloids.
✓

Answer

Colloid: A colloid is a heterogeneous mixture whose particles are not as small as solution but they are so small that cannot be seen by naked eye. When a beam of light is passed through a colloid then the path of the light becomes visible. For example milk, smoke etc.
Properties of a colloid:
  • A colloid is a heterogeneous mixture.
  • The size of particles of a colloid is too small to be individually seen by naked eyes. 
  • Colloids are big enough to scatter a beam of light passing through it and make its path visible. 
  • They do not settle down when left undisturbed, that is, a colloid is quite stable.
  • They cannot be separated from the mixture by the process of filtration. But, a special technique of separation known as centrifugation can be used to separate the colloidal particles.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Do as directed; [Che-1 M]" from Is Matter Around Us Pure→Is Matter Around Us Pure — all question types→Science STD 9 question papers→CBSE Board STD 9 question papers→CBSE Board question paper generator→

Similar questions

Calculate the molar mass of the following compounds:
MgO
→
‘A substance has a definite volume but no definite shape’. State whether this substance is a solid, a liquid or a gas.
→
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
  1. Both the Assertion and the Reason are correct and the Reason is the correct explanation of the Assertion.
  2. The Assertion and the Reason are correct but the Reason is not the correct explanation of the Assertion.
  3. Assertion is true but the Reason is false.
  4. The statement of the Assertion is false but the Reason is true.
Assertion: Medicine are easily absorbed by our body in colloidal form.
Reason: It is because they have large surface area and therefore, absorbed easily.
→
How much water should be added to 15 grams of salt to obtain 15 percent salt solution?
→
Classify the following as physical or chemical properties:
Metallic sodium is soft enough to be cut with a knife.
→
What is wrong with the following symbols? Give the correct symbol in case:
Hydrogen (Hg)
→
What is meant by caying that metals are sonorous?
→
Which of the following will show “Tyndall effect”?
  1. Salt solution.
  2. Milk.
  3. Copper sulphate solution.
  4. Starch solution.
→
Choose the solutions from among the following mixtures:
Soil, Sea-water, Air, Coal, Soda-water
→
What is the approximate radius of the particles of a solution?
→