Cell and Cell Organelles — Science STD 8 — Question

Give information About Food web.

Make a survey of your school according to the plan of disaster managment an write the pointwise information.

Explain Importance Of Blood donation.

Explain why rails have gaps at specific distances.

How will you show that metal oxides are basic in nature?

Write the characteristics of viruses.
Answer:

In an electric circuit, a battery and a bulb have been connected and the battery consists of two cells of equal potential difference. If the bulb is not glowing, then which tests will you perform in order to find out the reason for the bulb not glowing?

Wood, coal, petrol or cooking gas are burnt for producing energy. Carbon is the common substance that burns in all these fuels. The product carbon dioxide is formed when carbon combines with oxygen in the air during the combustion process. We cannot obtain fuel from carbon dioxide by employing any other method. Properties of carbon dioxide are altogether different from those of fuel. Hence, this change is a irreversible chemical change.
Word equation:
Carbon + Oxygen → Carbon dioxide

When a substance having mass 3 kg receives 600 cal of heat, its temperature increases by 10 °C. What is the specific heat of the substance?

How do you protect soil from being polluted?