In replacement reaction 

The reaction will be most favorable if M happens to be:

1.  K
2.  Rb
3.  Li
4.  Na

Match List I with List II for the composition of substances and select the correct answer using the code given below:

Code :

The compound A on heating gives a colourless gas and a residue that is dissolved in water to obtain B. Excess of CO₂ is bubbled through an aqueous solution of B. C is solid. Solid C on gentle heating gives back A. The compound A is:

1. Na₂CO₃

2. K₂CO₃

3. CaSO₄.2H₂O

4. CaCO₃

Among the following which one has the highest cation to anion size ratio?

1. CsF

2. LiF

3. NaF

4. CsI

The correct order of the mobility of the alkali metal ions in aqueous solution is:

1. $L{i}^{+}>N{a}^{+}>K^{+}>R{b}^{+}$

2. $N{a}^{+}>K^{+}>R{b}^{+}>L{i}^{+}$

3. $K^{+}>R{b}^{+}>N{a}^{+}>L{i}^{+}$

4. $R{b}^{+}>K^{+}>N{a}^{+}>L{i}^{+}$

The correct order of increasing thermal stability of K₂CO₃, MgCO₃, CaCO₃, and BeCO₃ is:

1. $BeC{O}_3<MgC{O}_3<K_{2}C{O}_3<CaC{O}_3$

2. $BeC{O}_3<MgC{O}_3<CaC{O}_3<K_{2}C{O}_3$

3. $MgC{O}_3<BeC{O}_3<CaC{O}_3<K_{2}C{O}_3$

4. $K_{2}C{O}_3<MgC{O}_3<CaC{O}_3<BeC{O}_3$

In the case of alkali metals, the covalent character decreases in the order:

1. MCl>Ml>MBr>MF

2. MF>MCl>MBr>Ml

3. MF>MCl>Ml>MBr

4. Ml>MBr>MCl>MF