Science Do as directed; [1 M ]

When a crystal of copper sulphate is placed at the bottom of a beaker containing water, the water slowly turns blue. Why?

Name one property which is shown by ammonium chloride but not by sodium chloride.

When sugar is dissolved in water, there is no increase in the volume. Which characteristic of matter is illustrated by this observation?

A piece of chalk can be broken into small particles by hammering but a piece of iron cannot be broken into small particles by hammering. Which characteristic of the particles of matter is illustrated by these observations?

Which single term is used to describe the mixing of copper sulphate and water kept in a beaker, on its own?

Name one property of liquids and gases which tells us that their molecules are moving constantly.

What is the mane of the process in which: A solid turns directly into a gas?

Out of solids, liquids and gases, which one has: Minimum spaces between particles?

Name two gases which are supplied in compressed form in homes and hospitals.

Even two or three crystals of potassium permanganate can impart colour to a very large volume of water. Which characteristic of particles of matter is illustrated by this observation?

‘A substance has a definite shape as well as a definite volume’. Which physical state is represented by this statement?

Define matter. Give four examples of matter.

In a beam of sunlight entering a room, we can sometimes see dust particles moving in a haphazard way in the air. Why do these dust particles move?

State one condition necessary to liquefy gases (other than applying high pressure).

Name the process by which a drop of ink spreads in a beaker of water.

Explain why, when a bottle of perfume is opened in a room, we can smell it even from a considerable distance.

What is the common name of solid carbon dioxide?

A substance has neither a fixed shape nor a fixed volume. State whether it is a solid, a liquid or a gas.

What are the characteristics of matter?

Out of solids, liquids and gases, which one has: Maximum interparticle attractions?

Define the following terms: Condensation

What are the two ways in which the physical states of matter can be changed?

Name two processes which provide the best evidence for the motion of particles in matter.

Arrange the following substances in increasing order of force of attraction between their particles (keeping the substance having them in imum force of attraction first): Water, Sugar, Oxygen

What is the general name of:
Fluid forms of matter?

Under what conditions heat can be given to a substance without raising its temperature?

Out of solids, liquids and gases, which one has: Maximum movement of particles?

Give one example of diffusion of gases in a liquid.

What is the name of the process due to which dry ice changes into carbon dioxide gas?

Explain why, the diffusion of a solid in another solid.

Bromine particles are almost twice as heavy as chlorine particles. Which gas will diffuse faster; bromine (vapour) or chorine? Explain your answer.

What is the scientific name of particles which make up matter?

When a crystal of potassium permanganate is placed in a beaker, its purple colour spreads throughout the water. What does this observation tell us about the nature of potassium permanganate and water?

Define the following terms: Melting

Explain how, the smell of food being cooked in the kitchen reaches us even from a considerable distance.

Why is solid carbon dioxide known as dry ice?

What is the mane of the process in which: A gas turns directly into a solid?

Define the following terms: Freezing

Name the temperature at which: A solid changes into a liquid.

What is the: Common unit of temperature.