Final answer:
The atomic radius in Group 15 of the periodic table decreases as the atomic number increases.
Step-by-step explanation:
As each successive element in Group 15 of the periodic table is considered in order of increasing atomic number, the atomic radius decreases.
Group 15 elements, also known as the pnictogens, include nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), and bismuth (Bi). The trend in atomic radius occurs due to the increasing positive charge in the nucleus as you move across the period. This results in a stronger attractive force on the electrons, causing the atomic radius to decrease.
For example, nitrogen has a smaller atomic radius than phosphorus because nitrogen has a higher effective nuclear charge (due to the addition of protons in the nucleus), which attracts the electrons more strongly and pulls them closer to the nucleus, resulting in a smaller atomic radius.
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