Question

Which of the following is an example of catenation?
(A). $C{ H }_{ 4 }$
(B). $CHO$
(C). $C{ Cl }_{ 2 }$
(D). ${ C }_{ 2 }{ H}_{ 6 }$

Answer 1

- Hint: The bonding of atoms in a molecule in which atoms are arranged in long chains is called catenation. There are various factors that affect this property of catenation. The compound having more than one carbon atom will have the catenation property.

Complete step-by-step solution -

We can see mostly the catenation in carbon compounds since carbon forms covalent bonds with other carbon atoms to form longer chains. At least two carbon atoms are required to exhibit the property of catenation else the chain would not form. As we can see that among the given options only ${ C }_{ 2 }{ H}_{ 6 }$ has more than one carbon atom while the rest of them have only one carbon atom. So, option D is the correct one.
The ability of the elements to exhibit catenation depends on many factors. Let us understand those factors.
The size of the element is a crucial factor for it to exhibit catenation. If the size of each atom is large then it cannot sustain longer chains.
The ability of catenation is also affected by the electronegativity of the elements. Highly electronegative elements attract the shared pair of electrons towards them and make the bond more polar. With polar bonds, formation of long chains is not possible as the electrons are not shared equally between two atoms.
The type of valence orbital is also an important factor for determining the ability of catenation. If the valence orbital has the least diffused shape, it can for longer bonds and thus can form longer bonded chains. The order of diffused shapes for orbitals are s < p < d < f. So, an element having valence electrons in s and p orbitals will have the ability to exhibit catenation.

Note: Don’t confuse yourself by thinking that the catenation property is limited to only carbons atoms. Along with carbon, we can also find the property of catenation in different elements such as silicon, sulphur and boron.