The most reactive state of hydrogen is –

(1) Atomic hydrogen                               

(2) Heavy hydrogen

(3) Molecular hydrogen                           

(4) Nascent hydrogen

In which of the following reactions is ${\mathrm{H}}_2{\mathrm{O}}_2$ acting as an acid.

(A) $2{\mathrm{KMnO}}_4+3{\mathrm{H}}_2{\mathrm{SO}}_4+5{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{K}}_2{\mathrm{SO}}_4+{\mathrm{MnO}}_4+2{\mathrm{MnSO}}_4+8{\mathrm{H}}_2\mathrm{O}+5{\mathrm{O}}_2$

(B) $2{\mathrm{K}}_3\mathrm{Fe}{\left(\mathrm{CN}\right)}_6+2\mathrm{KOH}+{\mathrm{H}}_2{\mathrm{O}}_2\to 2{\mathrm{K}}_4\mathrm{Fe}{\left(\mathrm{CN}\right)}_6+2{\mathrm{H}}_2\mathrm{O}+{\mathrm{O}}_2$

(C) ${\mathrm{O}}_3+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{H}}_2\mathrm{O}+2{\mathrm{O}}_2$

(D) $\mathrm{Ba} {\left(\mathrm{OH}\right)}_2+{\mathrm{H}}_2{\mathrm{O}}_2\to {\mathrm{BaO}}_2+{\mathrm{H}}_2\mathrm{O}$

Exhausted permutit does not contain ............ ion –

(A) ${\mathrm{Na}}^{+}$                                      

(B) ${\mathrm{Mg}}^{2+}$

(C) ${\mathrm{Al}}^{3+}$                                    

(D) ${\mathrm{Si}}^{4+}$

Which of the following metal cannot absorb hydrogen –

(1) Pd                                     

(2) Al

(3) Ni                                     

(4) Co

The best explanation for not placing hydrogen with the group of alkali metals or halogens is.

1. Hydrogen can form compounds with all other elements

2. Hydrogen is much lighter element than the alkali metals or the halogens

3. The IE of hydrogen is too high for group of alkali metals but too low for halogen group

4. None of these

The colour of hydrogen is –

1. Blue                           

2. Yellow

3. Orange                       

4. No colour

In which of the following compounds, hydrogen exists in the atomic state –

1. Metallic hydrides                           

2. Ionic hydrides

3. Molecular hydrides                       

4. Water

${}_1{}^2\mathrm{H}$ stands for –

(1) Protium                               

(2) Heavy water

(3) Deuterium                           

(4) Tritium

A substance gives off ${\mathrm{O}}_2$ when heated, turns an acid solution of $\mathrm{KI}$ violet, and reduces acidified ${\mathrm{KMnO}}_4$. The substance is –

1. ${\mathrm{SO}}_3$                            

2. ${\mathrm{KNO}}_3$

3. ${\mathrm{H}}_2{\mathrm{O}}_2$                          

4. All of these

100 ml of a sample of hard water required 25.1 ml of 0.02 (N) ${\mathrm{H}}_2{\mathrm{SO}}_4$ for complete reaction. What is the hardness of the given water sample ? (sp. gravity of given water sample = 1 gm/ml)

(A) 200 ppm                                 

(B) 250 ppm

(C) 251 ppm                                 

(D) 258 ppm