The correct order of increasing lattice energy of the metallic compounds is –

(1) NaCl < CaO < NaI < BaO               

 

(2) NaI < NaCl < BaO < CaO

(3) NaCl < NaI < BaO < CaO                 

(4) NaI < NaCl < CaO < BaO

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

The boiling point of calcium is abnormally high as compared to magnesium because-

1. In calcium d-orbital forms a weak metallic bond

2. In calcium p-orbital forms  a weak metallic bond

3. In calcium d-orbital forms a strong metallic bond

4. In calcium s-orbital forms  a strong metallic bond

The decreasing order of II ionisation energy of K, Ca, and Ba is –

(1) K > Ca > Ba                                   

(2) Ca > Ba > K 

(3) Ba > K > Ca                                   

(4) K > Ba > Ca

Two metals X and Y form covalent halides. Both halides can act as Lewis acids and a catalyst in Friedel Crafts reaction. Halide of X is polymer in the solid state and a dimer in the vapour state which decomposes to monomer at 1200 K. However, halide of Y is a dimer in vapour state and becomes ionic in polar solvent. X and Y are respectively.

(1) Be, Al                                             

(2) Al, Be

(3) Be, Ca                                             

(4) Mg, Ca

Which of the following compounds decomposes on heating similar to $LiN{O}_3$.

(1) $Ba{\left(N{O}_3\right)}_2$                               

(2) $Sr{\left(N{O}_3\right)}_2$

(3) $Mg{\left(N{O}_3\right)}_2$                               

(4) All

Solubility of sulphates in water decreases from $MgS{O}_4$ to $BaS{O}_4$. It is due to the fact that –

(1) Ionic nature increases

(2) Size of $M^{2+}$ ion increases

(3) Lattice energy decrease

(4) Hydration enthalpy of $M^{2+}$ ions decreases

In the Solvay process of manufacture of sodium carbonate, the raw materials used are :

1. Aqueous NaOH, $N{H}_3$ and $C{O}_2$

2. Molten NaOH, $N{H}_3$ and CO

3. Brine NaCl, $N{H}_3$ and CO

4. Brine NaCl, $N{H}_3$ and $C{O}_2$

A blue coluored solution of an alkali metal in liq NH₃ is due to the presence of -

1. ${\mathrm{M}}^{-}$atoms.                                         

2. ${\mathrm{M}}^{+}$ ions .

3. Solvated anions  .                           

4. Solvated electrons.

Alkali metal ions are- 

1. Diamagnetic and coloured.

2. Diamagnetic and colourless.

3. Paramagnetic and coloured.

4. Paramagnetic and colourless.