# Which element has the higher ionization energy; boron or oxygen?

Sep 8, 2016

Well, which has higher atomic number? $B ,$ $Z = 5$; $O ,$ $Z = 8$

#### Explanation:

We interrogate the process:

$\text{Atom(g) + energy}$ $\rightarrow$ $\text{Atom"^+(g) + "electron}$

Because oxygen has the higher atomic number, and is in the same Period, I am willing to bet that it has a higher first ionization energy.

See here.