Question

WRITE THE FOLLOWING
What are the two essential conditions of rusting? How does oiling prevent rusting?
2. Why does the cut surface of brinjal turn brown?
3. What are crystals? How can crystals of sodium chloride be prepared from common salt?
4. Rusting of iron is faster in rainy season as compared to other seasons . why?
5. When baking soda is mixed with vinegar, bubbles are formed with the evolution of a
gas. What type of change is it? Explain with word equation.
6. How can we prevent rusting?
7. What is rusting? Explain with a chemical equation. Is rusting a chemical change
?
8. Explain why burning of wood and cutting it into small pieces are considered as two
different types of changes.
9. Differentiate between physical and chemical changes.
10. When iron nail is dipped in copper suphate solution ,the blue colour of copper sulphate
changes to green . Explain the reason with the help of a chemical equation.
11. Classify the changes involved in the following processes as physical or chemical changes:​

Answer 1

Answer:

2. Because of iron content which rusts

3.

4.rusting requires moisture which is oxygen and water which is present in air in the rainy season

5. salt

6. by galvanization

7. rusting is the corrosion of iron in the presence of moisture.

Fe+H2O+O2→Fe2O3

8. Because while burning the wood goes under chemical change as its chemical properties change and while cutting it goes under physical change as its physical properties change.

9.physical properties change- physical change

chemical properties change-chemical change

10. the iron displaces copper as it is more reactive

11.u have not provided options

Explanation: