Question

Statement $1$ : $Si - Si$ bond is stronger than $Si - O$ bond.
Statement $2$ : Silicon cannot form $Si - Si$ double bond easily.
A.Statement $1$ is true, statement $2$ is true, the statement $2$ is the correct explanation for statement $1$.
B.Statement $1$ is true, statement $2$ is true, the statement $2$ is not a correct explanation for statement $1$ .
C.Statement $1$ is true and statement $2$ is false.
D.Statement $1$ is false and statement $2$ is true.

Answer 1

Silicon atoms can form four bonds same as that of carbon as they lie in the same column. It can either form ionic bonds or covalent bonds as it consists of four valence electrons.

Complete step by step answer:
-Statement $1$: $Si - Si$ bond is stronger than $Si - O$ bond.
-We will compare the bond energies of $Si - Si$ bond and $Si - O$ bond to see which bond is stronger.
-The bond energy of $Si - Si$ bond $= 230kJ$
-Bond energy of $Si - O$ bond $= 356kJ$
-Bond energy is defined as the amount of energy that is required to break one mole of a bond.
-The $Si - O$ bond is stronger compared to $Si - Si$ bond due to the higher overlapping and small size of the oxygen atom.
-Thus the above statement is false. $Si - Si$ bond is weaker than $Si - O$ bond.
-Statement $2$: Silicon cannot form $Si - Si$ double bond easily.
-The double bond that is formed between silicon is highly unstable because of its very large size.
-Because of the large atomic radius the p orbitals do not overlap with each other which makes it difficult to form double bonds.
-Hence, the given statement is true.
Therefore, the correct answer is option D i.e Statement $1$ is false and statement $2$ is true.

Note:
Even though the silicon is similar to carbon atoms, the size of the atom is very different as compared to carbon. That’s why the bonds in carbon atoms are formed easily as compared to the bond formation in silicon due to its larger atomic radius. The overlapping in silicon double bond takes place sideways from far due to its large size which leads to no bond formation .