SSLC (English Medium) Class 8 - Tamil Nadu Board of Secondary Education Question Bank Solutions for Science

Explain the role of yeast in making cakes and buns in a bakery?

Burning of fossil fuels is responsible for global warming. Justify the statement.

Do all the fruits and vegetables undergo browning? Explain.

Classify the following day-to-day activities based on chemical reactions by physical contact, solutions of reactants, heat, light, electricity, and catalyst.

1. Burning of crackers during festivals
2. Fading of coloured clothes on drying under sunlight.
3. Cooking of eggs.
4. Charging of batteries.

Kumar is going to build a house. To purchase the iron rods required for construction, he visited an iron and steel shop nearby. The seller showed him some iron rods which are fresh and good. He also showed him little older iron rods which are brownish in appearance. The price of fresh rods is more than the older ones. The seller also gave some offers to older ones. Kumar’s friend Ramesh advised him not to buy the cheaper rods.

1. Is Ramesh right in his suggestion?
2. Could you explain the reason for his suggestion?
3. What are the values shown by Ramesh?

Solubility of carbon dioxide in water is high when the

Give a reason for the following.

Aquatic animals can breathe in water.

How is water purified at a water purification plant?

Explain the environmental effects of chemical reactions?

Sodium hydroxide is a ______.

Bases are ______ in taste.

Chemical formula of calcium oxide is _______

Wasp sting contains _______.

Bases are soapy to touch when they are dry.

All bases are alkalis.

What are the similarities between acids and bases?

The chemical mixed with LPG that helps in the detection of its leakage is _______.

Which is known as syngas?

Producer gas is a mixture of _______ and _______.

______ is a prokaryotic microorganisms.