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Moderate

Periodic Trends

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Which of the following explains why the atomic radii DECREASE across a period?

A

As you move across the period, the number of protons increases, which increases the nuclear charge. The number of electrons remains the same creating a larger Coulombic attraction and decreasing the radii.

B

As you move across the period, the number of protons and electrons increases. The increased Coulombic attraction decreases the overall size of the atom.

C

As you move across the period, the number of protons remains constant while the number of electrons increases. The decreased Coulombic attraction decreases the overall size of the atom.

D

The atomic radii do not decrease across a period. It actually increases.