CBSE Class 9 Science Exploring Mixtures and Their Separation (Class 9 NCERT New) Quiz 6

1. State whether the following statement is True or False. Also, correct the False statements. (iii) In paper chromatography, the solvent level should be above the sample spot at the beginning of the experiment.

A True B False

2. State whether the following statement is True or False. Also, correct the False statements. (iv) Evaporation and crystallization are the same processes.

A True B False

3. Activity 5.6: Let us separateStep 2: Let it stand undisturbed. What do you observe? Can you explain why?

A The mixture separates into layers because the components have different densities. B The mixture remains completely mixed because the components have the same density. C The mixture evaporates completely leaving no residue. D The mixture changes color due to a chemical reaction.

4. Can you think of any heterogeneous mixtures with a gas as one of the components?

A Smoke in air B Salt dissolved in water C Pure oxygen gas D Sugar solution

5. What if two immiscible liquids of the same density are mixed in a separating funnel, how will the layers form?

A The liquids will not form separate layers and will mix completely. B The liquids will form two layers, but the layers will be indistinguishable due to equal density. C The liquids will form two layers, but the position of each layer cannot be determined. D The liquids will form two layers, with one always on top and the other at the bottom.

6. Immiscible liquids form two separate layers in a separating funnel because:

A they have different densities and do not mix with each other. B they react chemically to form new substances. C they have the same density and mix completely. D they dissolve in each other easily.

7. Sublimation is different from evaporation. Justify.

A Yes, sublimation and evaporation are different processes. B No, sublimation and evaporation are the same process. C Sublimation is a type of evaporation. D Evaporation only occurs in solids.

8. Refer to the diagram (Fig. 5.17: Sublimation of camphor). Identify the part labeled 'Glass funnel'.

A Cotton plug B Glass funnel C Wire gauze D Burner

9. Fill in the blank: The process in which a solid changes directly to the vapor state without passing through the liquid state is called _______.

A sublimation B condensation C melting D evaporation

10. Fill in the blank: On cooling, vapors condense back into a solid without becoming a liquid. This is called _______.

A deposition B evaporation C sublimation D melting