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. $\mathrm{MgO}$

The correct relation about the density of Na and K is 

1. Na > K                                                     

2. Na = K

3. K > Na                                                     

4. Li > K

In $K^{+}{F}^{-}$ ionic radius of $F^{-}$ is more while atomic radius of $K^{+}$ is –

(1) Less than $F^{-}$

(2) More than $F^{-}$

(3) Equal to $F^{-}$

(4) None of these

Lattice energy is lowest for –

1. LiF                                                       

2. NaCl

3. KBr                                                       

4. CsI

Which of the following halides has the highest melting point-

(A) NaCl                                           

(B) KCl

(C) NaBr                                           

(D) NaF

Alkaline earth metals form hydrated crystalline solids such as $MgC{l}_2.6H_{2}O,<mspace\; width="1em"></mspace>CaC{l}_2.6H_{2}O$. This is due to-

(1) Smaller ionic size

(2) Increased charge on ions

(3) Higher hydration enthalpies

(4) High oxidation potential

Magnesium can be prepared by heating-

(1) $MgC{l}_2$ with CaO at 1775 K

(2) $MgC{l}_2$ with $Ca{C}_2$ at 1775 K

(3) $MgC{l}_2$ with $Ca{\left(OH\right)}_2$ under pressure

(4) MgO with $Ca{C}_2$ at ordinary temperature

A chloride dissolves appreciably in cold water. When placed in a platinum wire in Bunsen flame no distinctive colour is noticed. Which cation could be present –

(1) $B{e}^{2+}$                                         

(2) $B{a}^{2+}$

(3) $P{b}^{2+}$                                         

(4) $C{a}^{2+}$

Which of the following is a false statement-

(1) Sodium oxide is more basic then magnesium oxide.

(2) Beryllium oxide is amphoteric

(3) The thermal stability of beryllium carbonate is more than that of calcium carbonate

(4) Beryllium is amphoteric

Which alkali metal has the lowest melting point and exists as a liquid  at 30 degree temp–

(1) Na                                                             

(2) K 

(3) Rb                                                             

(4) Cs