Physical Properties of Carbon Family

Q.

Why are Carbon $-$ Carbon bonds very strong and stable$?$

Q. Which of the following statement is incorrect for group 15 elements ?

1. The boiling point and melting point increases from top to bottom in the group
2. Dinitrogen is a gas while all others are solids
3. Order of ionization enthalpies is ${\Delta }_i{H}_1<{\Delta }_i{H}_2<{\Delta }_i{H}_3$
4. All of the above

Q. Which of the following compound has higher enol content?

1. 
2. 
3. 
4. 

Q. Which of the following has the maximum covalent radii?

1. Ge

2. Sn

3. C

4. Si

Q. $Ge\left(II\right)$ compounds are powerful reducing agents where as $Pb\left(IV\right)$ compounds are strong oxidants. It can be due to:

1. $Pb\text{is more electronegative than}Ge$
2. $\text{Ionisation potential of lead is less than that of}Ge$
3. $\text{Ionic radii of}P{b}^{2+}andP{b}^{4+}\text{are larger than those of}G{e}^{2+}andG{e}^{4+}$
   
4. $\text{More pronounced inert pair effect in lead than in}Ge$

Q.

The elements which occupy the peaks of ionisation energy curve, are

1. Na, Mg, Cl, L

2. Cl, Br, I, F

3. Na, K, Rb, Cs

4. He, Ne, Ar, Kr

Q.

The stability of +2 oxidation state is maximum in

1. Ge

2. Sn

3. Pb

4. C

Q. Why the atomic radii of the second and third transition series are almost same?

Q.

Among group 14 elements, the one having the lowest melting point is:

1. C

2. Si

3. Sn

4. Pb

Q.

The order in which the atomic radius increases is as follows

1. 
2. 
3. 
4. 

Q. Which of the following has the smallest atomic radii?

1. B

2. C

3. Al

4. Si