Question

COLUMN A COLUMN B 1. Manganese dioxide a. Enzyme 2. Heat evolved b. New substance 3. Chemical change c. Exothermic reaction 4. Hydrogen sulphide d. Catalyst 5. Amylase e. Rotten-egg smell ​

Answer 1

Answer:

• 1. Manganese dioxide - d. catalyst
• 2. Heat evolved -c. Exothermic reaction
• 3. Chemical change -b. New substance
• 4. Hydrogen sulphide -e. Rotten-egg smell
• 5. Amylase -a. enzyme

Answer 2

1. Manganese dioxide : (d) catalyst

• Manganese dioxide is the basic compound that acts as a catalyst in reactions such as decomposition of hydrogen peroxide into oxygen and water.

2. Heat evolved : (c) Exothermic reaction

• Exothermic reactions are the ones in which heat is evolved (low or enormous) along with the formation of products.

3. Chemical change : (b) New substance

• The changes which cannot be reversed back into the reactants are known as chemical changes and a new substance is formed.

4. Hydrogen sulphide : (e) Rotten-egg smell

• Hydrogen sulphide is a chemical gas that smells like eggs that are rotten.

5. Amylase : (a) enzyme

• Amylase is an enzyme that is found in the pancreas and salivary glands and helps digest food.