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Select the correct answer from A, B, C, D & E for the statement given below :
A non-metal that is lustrous.
Concept: undefined >> undefined
Select the correct answer from A, B, C, D & E for the statement given below :
A mixture consisting of elements & a compound.
Concept: undefined >> undefined
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Select the correct answer from A, B, C, D & E for the statement given below :
A noble gas.
Concept: undefined >> undefined
Match the separation of components in List I with the most appropriate process in List II.
| List I | List II |
| 1. Naphthalene from naphthalene & sodium chloride. | A: Separating funnel |
| 2. Cream from milk. | B: Sublimation |
| 3. Kerosene oil from kerosene oil & water. | C: Boiling |
| 4. Lead nitrate from an aqueous solution of lead nitrate. | D: Centrifugation |
| 5. Ammonia from an aqueous solution of ammonia. | E: Distillation |
Concept: undefined >> undefined
The diagram represents fractional distillation for the separation of mixtures. Answer the following :

- Can two immiscible liquids be separated by this process?
- Separation of liquids by this process is based on which physical property?
- If methyl alcohol & water are to be separated, which liquid would remain in flask ‘X’ after condensation.
- Give a reason for the above answer.
- State the purpose of the fractionating column in the apparatus.
Concept: undefined >> undefined
Select the correct answer from the choice given below to complete the sentence :
Dust in air is an example of _________ mixture.
Concept: undefined >> undefined
Select the correct answer from the choice given below to complete the sentence :
Compounds are ____________ in nature.
Concept: undefined >> undefined
Select the correct answer from the choice given below to complete the sentence :
An example of a monoatomic molecule is ___________.
Concept: undefined >> undefined
Give a reason for the following statement :
The filter paper made into a cone & placed in a funnel for filtering out the solid particles in a solid-liquid mixture should be moistened before placing it.
Concept: undefined >> undefined
Give a reason for the following statement :
Brass & bronze are examples of mixtures, while copper sulphate & lead nitrate are examples of compounds.
Concept: undefined >> undefined
Tick the most appropriate answer
2. Melting of ice is a
- reversible change
- irreversible change
- chemical change
- none of these
Concept: undefined >> undefined
Choose the most appropriate answer.
Rising and setting of the sun at a given place is a
Concept: undefined >> undefined
Tick the most appropriate answer.
3. Physical changes are
- permanent.
- periodic,
- temporary
- irreversible.
Concept: undefined >> undefined
Tick the most appropriate answer.
4. Chemical changes involve
- change in shape.
- change in size.
- change in molecular composition.
- none of these
Concept: undefined >> undefined
Tick the most appropriate answer.
5. Photosynthesis requires
- heat energy.
- wind energy
- sunlight.
- sound energy
Concept: undefined >> undefined
Fill in the blank
change in which the substance can be brought back to its original state is called a ............... change.
Concept: undefined >> undefined
Fill in the blank.
Changes that occur in nature are called ........................
Concept: undefined >> undefined
Fill in the blank.
An earthquake is a .................. change.
Concept: undefined >> undefined
Fill in the blank.
A new substance is formed in a ............... change.
Concept: undefined >> undefined
Fill in the blank.
Heat is .................... by a gas during the process of condensation.
Concept: undefined >> undefined
