Periodic Table

Question 1

What happens to atomic size across a period?

Answer 1

Decreases due to increased nuclear charge.

As you move from left to right across a period, the number of protons increases, pulling the electrons closer to the nucleus and reducing atomic size.

Question 2

What happens to atomic size down a group?

Answer 2

Increases due to more electron shells.

Each subsequent element down a group has an additional electron shell, which increases the distance between the outermost electrons and the nucleus.

Question 3

What happens to electronegativity across a period?

Answer 3

Increases due to more attraction for electrons.

As the nuclear charge increases, the ability of an atom to attract electrons in a bond also increases.

Question 4

What happens to ionization energy down a group?

Answer 4

Decreases (electrons are farther from the nucleus).

The increased distance of the outer electrons from the nucleus results in a weaker attraction, making it easier to remove an electron.