Question

Which of the following statements about the energy of hybrid orbitals resulting from mixing of $2s$ and $2p$ orbitals is true?

• A. $E2p>Es{p}^3>Es{p}^2>Esp>E2s$
• B. $Es{p}^3>Es{p}^2>Esp>E2p>E2s$
• C. $E2p>Esp>Es{p}^2>Es{p}^3>E2s$
• D. $E2p>Esp>E2s>Es{p}^2>Es{p}^3$

Answer 1

Answer: (A)

$E2p>Es{p}^3>Es{p}^2>Esp>E2s$

$2p$ has higher energy than $2s$, Hence, more the $p$ character, higher is the energy. However hybrid orbitals are lower in energy than the basic orbitals. Therefore required order is:

$E_{2p}>E_{s{p}^3}>E_{s{p}^2}>E_{sp}>E_{2s}$