$$\begin{gathered} \mathrm{Fe}+{\mathrm{H}}_2\mathrm{O}<mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>\stackrel{1023-1073\mathrm{K}}{\to }<mspace\; width="1em"></mspace>\mathrm{Product} \\ <mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace><mspace\; width="1em"></mspace>\left(\mathrm{Steam}\right) \\ \mathrm{Product}<mspace\; width="1em"></mspace>\mathrm{formed}<mspace\; width="1em"></mspace>\mathrm{is}<mspace\; width="1em"></mspace>- \\ 1.<mspace\; width="1em"></mspace>\mathrm{FeO}+{\mathrm{H}}_2 \end{gathered}$$

2. ${\mathrm{Fe}}_2{\mathrm{O}}_3+{\mathrm{H}}_2\mathrm{O}$

3. ${\mathrm{Fe}}_2{\mathrm{O}}_3+{\mathrm{H}}_2$

4. ${\mathrm{Fe}}_3{\mathrm{O}}_4+{\mathrm{H}}_2$

Hydrogen is placed separately in the periodic table because : 

1. It resembles alkali metals.

2. It shows the same reactions as halogens.

3. Both (1) and (2)

4. None of the above.

The following reaction is an example of :

\(2 \mathrm{MnO}_4^{-}+6 \mathrm{H}^{+}+5 \mathrm{H}_2 \mathrm{O}_2 \rightarrow 2 \mathrm{Mn}^{2+}+8 \mathrm{H}_2 \mathrm{O}+5 \mathrm{O}_2\)

1. Hydrolysis reaction

2. Redox reaction

3. Disproportionation reaction

4. None of the above

The incorrect statement among the following options is:

1. K⁺ ions react with alkaline water and give K(OH)₃

2. KCl is a salt of strong acid and strong base.

3. Al(OH)₃ in alkaline condition gives [Al(OH)₄]^-

4. AlCl₃ is a salt of strong acid and weak base.

The catalyst used to increase the production of H₂ , by ‘coal gasification' process is -

1. Copper 

2. FeCr₂O₄ (iron chromate) 

3. Pd/C 

4. None of the above.

The softening of hard water by synthetic ion-exchange resins is based on -

1. Increasing the lattice energy.

2. Physical separation.

3. Lowering the activation energy.

4. Exchange of cations and anions.

The temporary and permanent hardness of water is caused by -
1. Permanent hardness is caused by hydrogen carbonates and temporary hardness is caused by chlorides.
2. Temporary hardness is caused by dihydrogen and permanent hardness is caused by oxides.
3. Temporary hardness is caused by insoluble hydrogen carbonates and permanent hardness is caused by chlorides.
4. Temporary hardness is caused by hydrogen carbonates and permanent hardness is caused by chlorides.

CO2  is used as a fire extinguisher because -

1. ${\mathrm{CO}}_2$ has high lattice energy.

2. ${\mathrm{CO}}_2$ will be effective in isolating the burning surface from dihydrogen and dioxygen.

3. ${\mathrm{CO}}_2$ is lighter than dioxygen.

4. ${\mathrm{CO}}_2$ is lighter than dihydrogen.

Atomic hydrogen or oxy-hydrogen torch is used for cutting and welding purposes because:

Metallic hydrides are useful for hydrogen storage because : 

1. Metallic hydrides are oxygen-rich.

2. Metallic hydrides are oxygen-deficient.

3. Metallic hydrides are hydrogen-rich.

4. Metallic hydrides are hydrogen-deficient.