Which is not correctly matched?

(1) Basic strength of oxides                                 ${\mathrm{Cs}}_2\mathrm{O}<{\mathrm{Rb}}_2\mathrm{O}<{\mathrm{K}}_2\mathrm{O}<{\mathrm{Na}}_2\mathrm{O}<{\mathrm{LiO}}_2$

(2) Stability of peroxides                                      ${\mathrm{Na}}_2\mathrm{O} <{\mathrm{K}}_2{\mathrm{O}}_2<{\mathrm{Rb}}_2{\mathrm{O}}_2<{\mathrm{Cs}}_2{\mathrm{O}}_2$

(3) Stability of bicarbonate                                   ${\mathrm{LiHCO}}_3<{\mathrm{NaHCO}}_3<{\mathrm{KHCO}}_3<{\mathrm{RbHCO}}_3<\mathrm{Cs} {\mathrm{HCO}}_3$

(4) Melting Point                                                  $\mathrm{NaF}<\mathrm{NaCl}<\mathrm{NaBr}<\mathrm{Nal}$

 

(A) 1 and 4                                           

(B) 1 and 3

(C) 1 and 2                                           

(D) 2 and 3

Which of the following reactions of potassium superoxide supply oxygen gas in the breathing equipments used in space and submarines?

(1) Reaction of superoxide with nitrogen in the exhaled air.

(2) Reaction of superoxide with moisture in the exhaled air.

(3) Reaction of superoxide with carbon dioxide in the exhaled air

(1) (1), (2) and (3)                                       

(2) (2) and (3) only

(3) (2) only                                                 

(4) (1) and (2) only

Which of the following acts as an oxidizing as well as a reducing agent?

(1) ${\mathrm{Na}}_2\mathrm{O}$                                     

(2) ${\mathrm{NaO}}_3$

(3) $\mathrm{NaNO}$                                     

(4) ${\mathrm{NaNO}}_2$

Alkaline earth metal nitrates on heating decompose to give:

(1) $\mathrm{M}{\left({\mathrm{NO}}_2\right)}_2 \mathrm{and} {\mathrm{O}}_2 \mathrm{only}$                                   

(2) $\mathrm{MO}, {\mathrm{N}}_2 \mathrm{and} {\mathrm{O}}_2$

(3) $\mathrm{MO}, {\mathrm{NO}}_2 \mathrm{and} {\mathrm{O}}_2$                                         

(4) $\mathrm{MO} \mathrm{and} {\mathrm{NO}}_2 \mathrm{only}$

A metal [X] heating on nitrogen gas gives [Y]. [Y] on treatment with ${\mathrm{H}}_2\mathrm{O}$ gives a colourless gas which when passed through ${\mathrm{CuSO}}_4$ solution gives a blue colour. [Y] is-

1. $\mathrm{Mg}{\left({\mathrm{NO}}_3\right)}_2$                                     

2. ${\mathrm{Mg}}_3{\mathrm{N}}_2$

3. ${\mathrm{NaN}}_3$                                             

4. $\mathrm{MgO}$

Assertion : Beryllium resembles aluminium.

Reason : : Charge / radius of $B{e}^{2+}$ ion is nearly the same as that of the $A{l}^{3+}$ ion.

Assertion : As the electropositive character increases down the group, the stability of carbonates and hydrogen carbonates of alkali metals increases.

Reason : Lithium carbonates is not so stable to heat ; lithium being very small in size polarizes a large $C{O}_3^{2-}$ion leading to the formation of more stable $L{i}_{2}O$ and $C{O}_2$.

The following is the correct order of chemical reactivity with water according to electrochemical series-

1. K>Mg>Cu>Zn                                     

2. K>Mg>Zn>Cu

3. Cu>Zn>K>Mg                                     

4. Mg>K>Cu>Zn

In the reaction $\mathrm{M}+{\mathrm{O}}_2\to {\mathrm{MO}}_2$ (superoxide) the metal is -

1. Li                 

2. Na

3. K                 

4. Ba 

The reaction of sodium with water is highly exothermic. The rate of reaction can be lowered by-

(1) Decreasing the temperature 

(2) Mixing with alcohol

(3) Mixing with acetic acid 

(4) Making an amalgam