Final answer:
The bonding in N2 involves a strong triple bond with six shared electrons, making it inert, whereas NH3 has a lone pair on the nitrogen atom, forming a trigonal pyramidal shape and allowing for hydrogen bonding.
Step-by-step explanation:
The bonding in N2 is fundamentally different from the bonding in NH3 due to the types of bonds and electron distributions in each molecule. N2 has a very strong triple bond between the two nitrogen atoms, which makes it very unreactive.
This triple bond involves the sharing of six electrons between the nitrogen atoms. In contrast, NH3 (ammonia) has a single lone pair of electrons on the nitrogen and three single bonds between nitrogen and hydrogen atoms. The nitrogen atom in NH3 also acquires a partial negative charge, not a positive charge as may be incorrectly stated, because it is more electronegative than hydrogen. The hydrogen atoms, in turn, acquire a partial positive charge.
In NH3, which can be compared to SO2, the lone pair of electrons occupies a larger region of space than a bonding pair of electrons, giving ammonia a trigonal pyramidal shape. This also affects the molecule's properties, such as its ability to engage in hydrogen bonding with water, which is unlike N2's nonpolar and inert nature. Furthermore, the bonding in NH3 can be described using sp3 hybrid atomic orbitals, formed from the hybridization of the nitrogen's 2s and 2p orbitals. This results in four hybrid orbitals, of which three are used for bonding with hydrogen atoms and one contains the lone pair of electrons.