The Lewis structure of $\mathrm{N}_2$ indicates that the nitrogen-to-nitrogen bond is a triple covalent bond. Other evidence suggests that the $\sigma$ bond in this molecule involves the overlap of $s p$ hybrid orbitals. (a) Draw orbital diagrams for the $\mathrm{N}$ atoms to describe the bonding in $\mathrm{N}_2$.

The effect of temperature change on the electrical conductivity of ultrapure silicon is quite different from that on silicon containing a minute trace of arsenic. Why is this so?

Explain whether the addition of gallium arsenide in trace amounts to germanium, would produce a $n$-type semiconductor.

Explain whether the addition of arsenic in trace amounts to germanium, would produce a $n$-type semiconductor.

Explain whether the addition of cadmium sulfide in trace amounts to germanium, would produce a $n$-type semiconductor.

Explain whether the addition of tin in trace amounts to germanium, would produce a $n$-type semiconductor.

Explain whether the addition of aluminium in trace amounts to germanium, would produce a $n$-type semiconductor.

Construct the molecular orbital diagram for SrCl. Would you expect the bond length of SrCl$^+$ to be longer or shorter than that of SrCl?

Explain whether the addition of sulfur in trace amounts to germanium, would produce a $n$-type semiconductor.

Explain whether the addition of gallium in trace amounts to silicon, would produce a $p$-type semiconductor.

Explain whether the addition of gallium arsenide in trace amounts to silicon, would produce a $p$-type semiconductor.

Explain whether the addition of boron in trace amounts to silicon, would produce a $p$-type semiconductor.

In which of the following, $\mathrm{CO}_3^{2-}, \mathrm{SO}_2, \mathrm{CCl}_4, \mathrm{CO}$, $\mathrm{NO}_2{ }^{-}$, would you expect to find $s p^2$ hybridization of the central atom? Explain.

Explain whether the addition of lead in trace amounts to silicon, would produce a $p$-type semiconductor.