Preparation of Dioxygen

Q.

What happens when iron reacts with a concentrated nitric acid?

1. Ferric nitrite is formed.

2. Ferrous hydroxide is formed.

3. Ferric oxide is formed.

4. Ferric nitrate is formed.

Q.

The reaction of $\mathrm{NO}\mathrm{with}{\mathrm{N}}_2{\mathrm{O}}_4\mathrm{at}250\mathrm{K}$ gives

1. ${\mathrm{N}}_2\mathrm{O}$

2. ${\mathrm{NO}}_2$

3. ${\mathrm{N}}_2{\mathrm{O}}_5$

4. ${\mathrm{N}}_2{\mathrm{O}}_3$

Q.

Name the process by which impure ore of aluminum gets purified by using a concentrated solution of an alkali.

Q. Which of the following release oxygen on heating at high temperature?

1. 
2. 
3. 
4. All of these

Q.

Oxygen is not evolved when:

1. Sodium peroxide reacts with water

2. Ammonium nitrate is heated

3. Zinc oxide is treated with $NaOH$

4. Potassium chlorate is heated with $Mn{O}_2$ catalyst.

Q.

Finely divided metals and metal oxides on reaction with hydrogen peroxide liberate __ gas.

Q.

Name one metal which on heating reacts at a fairly good speed with steam to liberate hydrogen.