```latex
\begin{tabular}{|c|c|c|c|}
\hline
Element & Ionization Energy (kJ/mole) & Element & Ionization Energy (kJ/mole) \\
\hline
H & 1311 & Na & 496 \\
\hline
He & 2370 & Mg & 737 \\
\hline
Li & 521 & Al & 576 \\
\hline
Be & 899 & Si & 786 \\
\hline
B & 799 & P & 1052 \\
\hline
C & 1087 & S & 1000 \\
\hline
N & 1404 & Cl & 1245 \\
\hline
O & 1314 & Ar & 1521 \\
\hline
F & 1682 & K & 419 \\
\hline
Ne & 2080 & Ca & 590 \\
\hline
\end{tabular}
```



Answer :

To determine the ionization energies for the given elements, let's analyze the provided data step-by-step. Here is a detailed breakdown organized into a table format for clarity:

[tex]\[ \begin{array}{|c|c|} \hline \text{\textbf{Element}} & \text{\textbf{Ionization Energy (kJ/mole)}} \\ \hline \text{H} & 1311 \\ \hline \text{He} & 2370 \\ \hline \text{Li} & 521 \\ \hline \text{Be} & 899 \\ \hline \text{B} & 799 \\ \hline \text{C} & 1087 \\ \hline \text{N} & 1404 \\ \hline \text{O} & 1314 \\ \hline \text{F} & 1682 \\ \hline \text{Ne} & 2080 \\ \hline \text{Na} & 496 \\ \hline \text{Mg} & 737 \\ \hline \text{Al} & 576 \\ \hline \text{Si} & 786 \\ \hline \text{P} & 1052 \\ \hline \text{S} & 1000 \\ \hline \text{Cl} & 1245 \\ \hline \text{Ar} & 1521 \\ \hline \text{K} & 419 \\ \hline \text{Ca} & 590 \\ \hline \end{array} \][/tex]

### Explanation of Ionization Energy:
- Ionization energy is the energy required to remove an electron from a gaseous atom or ion.
- Generally, ionization energy increases across a period (left to right on the periodic table) due to increasing nuclear charge.
- It decreases down a group (top to bottom on the periodic table) as the outer electrons are farther from the nucleus and experience more shielding.

### Summary of Ionization Energies:
1. Alkali Metals: Li (521), Na (496), K (419)
- Ionization energies are relatively low as they have one electron in their outermost shell.

2. Noble Gases: He (2370), Ne (2080), Ar (1521)
- High ionization energies due to full valence shells, making them stable and inert.

3. Other Elements:
- Be (899), Mg (737), Ca (590): These are alkaline earth metals with slightly higher ionization energies than alkali metals.
- Transition Metals and Metalloids: Al (576), Si (786)
- Non-Metals: B (799), C (1087), N (1404), O (1314), F (1682), P (1052), S (1000), Cl (1245)

By observing and analyzing the pattern, we can gain insights into periodic trends and electron configurations across different elements.