Explain the following observations: (a) \(\mathrm{HNO}_{3}\) is a stronger oxidizing agent than \(\mathrm{H}_{3} \mathrm{PO}_{4}\). (b) Silicon can form an ion with six fluorine atoms, \(\mathrm{SiF}_{6}^{2-}\), whereas carbon is able to bond to a maximum of four, \(\mathrm{CF}_{4}\). (c) There are three compounds formed by carbon and hydrogen that contain two carbon atoms each \(\left(\mathrm{C}_{2} \mathrm{H}_{2}, \mathrm{C}_{2} \mathrm{H}_{4},\right.\) and \(\left.\mathrm{C}_{2} \mathrm{H}_{6}\right),\) whereas silicon forms only one analogous compound \(\left(\mathrm{Si}_{2} \mathrm{H}_{6}\right)\).

The difference in the chemical properties and bonding in the given observations can be explained as follows: (a) HNO3 is a stronger oxidizing agent than H3PO4 due to the higher oxidation state and electronegativity of nitrogen compared to phosphorus, making it more likely to accept electrons. (b) Silicon can form SiF6^2- with six fluorine atoms because of its access to 3d orbitals, allowing for an expanded octet, while carbon is limited to a maximum of four bonded atoms in CF4 due to its available 2s and 2p orbitals. (c) Carbon can form three various compounds with hydrogen (C2H2, C2H4, C2H6) due to its ability to undergo multiple types of hybridization and form single, double, and triple bonds, whereas silicon forms only one analogous compound with hydrogen (Si2H6) as it does not readily form multiple bonds.