Secondary School (English Medium) (5 to 8) इयत्ता ८ - CBSE Question Bank Solutions

If the metal clip used in the electroscope is replaced by an ebonite rod and a charged body is brought in contact with it, will there be any effect on the aluminium strips? Explain.

Damaged seeds would _________ on top of water.

For growing a crop, sufficient sunlight and _________ and _________ from the soil are essential.

Write a paragraph in your own words of the following.

Sowing

Name the microorganisms which can fix atmospheric nitrogen in the soil.

Write 10 lines on the usefulness of microorganisms in our lives.

Write a short paragraph on the harmful effects of microorganisms.

Fill in the blanks with appropriate words.

Like synthetic fibres, plastic is also a _______

Explain why plastic containers are favoured for storing food.

Explain the difference between thermoplastic and thermosetting plastics.

Explain why the following is made of thermosetting plastics.

Saucepan handles

Give examples to show that plastics are non-corrosive in nature.

Should the handle and bristles of a tooth brush be made of the same material? Explain your answer.

Describe an activity to show that thermoplastic is a poor conductor of electricity.

Name the petroleum product used for surfacing of roads.

Process of separation of different constituents from petroleum is called ______.

Kerosene is not a fossil fuel.

Explain the process of formation of petroleum.

Explain how the use of CNG in automobiles has reduced pollution in our cities.

Compare LPG and wood as fuels.