Final answer:
The atoms are ordered from smallest to largest ionization energy as follows: Na, Mg, P, Cl, and Ar. This is based on their positioning in the periodic table, with Na being the farthest left and top and Ar being a noble gas with the highest ionization energy.
Step-by-step explanation:
To order the atoms and ions according to increasing ionization energy, we must consider their positions in the periodic table. Ionization energy generally increases across a period (from left to right) and decreases down a group (from top to bottom). Therefore, generally, elements on the left side of a period will have lower ionization energies compared to elements on the right side of the same period, and elements located at the bottom of the periodic table will have lower ionization energies than those above them.
According to these trends, the order of increasing ionization energy, from the smallest to the largest, is:
- Na (Sodium)
- Mg (Magnesium)
- P (Phosphorus)
- Cl (Chlorine)
- Ar (Argon)
This order reflects the position of these atoms on the periodic table, with sodium being on the far left of a period and argon being a noble gas with a fully filled valence shell, which gives it a very high ionization energy.