English Medium Class 9 - CBSE Question Bank Solutions for Science

Which of the two diffuses faster : a liquid or a gas?

State whether the following statement is true or false :

Red-brown bromine vapour diffuse into air in a gas jar but the colourless air molecules do not diffuse into bromine vapour.

A bottle of perfume was opened in a room. The smell of its vapours spread in the entire room. Name the property of gases which is responsible for this behaviour of perfume vapours.

If the fish is being fried in a neighbouring home, we can smell it sitting in our own home. Name the process which brings this smell to us.

Fill in the following blank with suitable words :

Solid, liquid and gas are the three ........................ of matter.

Fill in the following blank with suitable words :

At room temperature, the forces of attraction between the particles of solid substances are ....................... then those which exist in the gaseous state.

Explain the various factors which are responsible for the loss of stored food grains.

Explain the various preventive measures which are taken before storing the food grains.

Which of the following diffuses fastest and which the slowest?
Solid, Liquid, Gas Give reasons for your answer.

How does fumigation differ from spraying ?

Write down three unique characteristics of storage structure.

Name the three states of matter. Give one example of each.

State two characteristic properties of a gas.

Describe how drying of food grains is done.

As an incharge of a grain store, how will you find out the presence of pests ?

Describe the various methods of controlling pests attacking stored grains.

Why do gases have neither a fixed shape nor a fixed volume?

Give two reasons to justify that Water is a liquid at room temperature.

When an incense stick (agarbatti) is lighted in one corner of a room, its fragrance quickly spreads in the entire room. Name the process involved in this.

A girl is cooking some food in the kitchen. The smell of food being cooked soon reaches her brother's room. Explain how the smell could have reached her brother's room.