A hydrated water soluble salt, A in solution gives a turbidity with dilute hydrochloric acid evolving a gas with a suffocation odour. The solution of A decolourises lodine solution. A is likely to be

1. KI                                         

2. $N{a}_{2}S{O}_4.10H_{2}O$

3. $N{a}_2{S}_2{O}_3.5H_{2}O$                   

4. $AgN{O}_3$

Which of the following compounds may be soluble in pyridine-

(1) Barium chloride                             

(2) Sodium chloride

(3) Lithium chloride                           

(4) Potassium chloride

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

The basic character of oxides MgO, SrO, $K_{2}O$, NiO and $C{s}_{2}O$ increases in the order –

(1) $MgO>SrO>K_{2}O>NiO>C{s}_{2}O$

(2)  $C{s}_{2}O>K_{2}O>MgO>SrO>NiO$

(3) $NiO<MgO<SrO<K_{2}O<C{s}_{2}O$

(4) $K_{2}O<NiO<MgO<SrO<C{s}_{2}O$

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