Carbon

1. Carbon monoxide is used as a reducing agent in metallurgy but not carbon dioxide. Why?

2. Give the laboratory method of preparation of carbon monoxide.

3. Define the terms ‘allotropes’ with examples.

4. What happens when carbon monoxide is passed over heated finely divided nickel?

5. What happens when a piece of burning magnesium is dropped into a jar full of carbondioxide?

6. What happens when oxalic acid crystals are heated with concentrated sulphuric acid?

7. Why is carbon used as the most common reducing agent in thermal metallurgy?

8. What is dry ice? Why it is called so?

9. Why is carbon monoxide extremely poisonous?

10. Give examples of crystalline allotropes of Carbon.

11. Write a chemical reaction to show the reducing action of CO.

12. How would you convert CO into CO₂ and vice versa?

13. What happens when Carbon monoxide is heated with hydrogen in presence of ZnO and Cu?

14. Name the latest discovered allotropic form of carbon.

15. What happens when:

(a) Carbon monoxide is passed over finely divided nickel at 80°C.

(b) A gas obtained from a mixture of marble and dilute hydrochloric acid is passed into lime water till excess.

(c) A gas obtained form a mixture of copper turnings and hot conc. Sulphric acid is passed into chlorine water.

(d) Carbon monoxide is passed over finely divided nickel.