Which of the following ions is the best conductor of electricity in aqueous solution –

(1) $L{i}^{+}$                                           

(2) $N{a}^{+}$

(3) $C{s}^{+}$                                         

(4) $K^{+}$

Among the following, the incorrect statement is–

1. Lithium is the softest among all the alkali metals

2. Lithium possesses higher melting and boiling points

3. It is least reactive among alkali metals

4. It forms chloride which is soluble in alcohol

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 $C{O}_2$