Change in Colour and State

Q. Which of the following things change during curdling of milk?

1. State
2. Colour
3. Weight
4. Taste

Q.

.A substance which is formed on heating iron filings with sulphur powder.

Q. A chemical change is involved in the image given below.

1. True
2. False

Q. When iron filings are added to copper sulphate solution, a confirms the occurrence of a chemical change.

1. evolution of gas
2. evolution of heat
3. change in colour

Q. Match the correct pairs.

1. 
2. 
3. 
4. 
5. 
6. 

Q. When iron nail is dipped in a blue coloured copper sulphate solution then:

1. the colour of the solution changes to red.
2. the colour of the solution changes to green.
3. the copper is deposited on the iron nail.
4. a chemical change occurs.

Q. Identify the chemical changes.

1. Rusting of iron
2. Cooking an egg
3. Burning of paper
4. Baking a cake
5. Souring of milk
6. Melting of ice
7. Folding a paper
8. Boiling water