PERIODIC TRENDS

Front

What is ionization energy?

Back

Ionization energy is the amount of energy required to remove an electron from an atom in its gaseous state.

Front

Which element has the lowest ionization energy in Group 1?

Back

Francium (Fr) has the lowest ionization energy in Group 1.

Front

Why does Francium have the lowest ionization energy in Group 1?

Back

Its 1 valence electron is very far from the nucleus, so little energy is needed to remove it.

Front

What trend is observed in ionization energy as you move across a period from left to right?

Back

Ionization energy generally increases as you move from left to right across a period.

Front

What is the atomic radius?

Back

The atomic radius is the distance from the nucleus of an atom to the outermost shell of electrons.

Front

Which element has the largest atomic radius in Period 4?

Back

Potassium (K) has the largest atomic radius in Period 4.

Front

What happens to atomic radius as you move across a period from left to right?

Back

The atomic radius decreases as you move from left to right across a period.

Front

Why does atomic radius decrease across a period?

Back

The number of protons increases, leading to a greater positive charge that attracts electrons more strongly.

Front

What is the trend in atomic radius as you move down a group?

Back

The atomic radius increases as you move down a group.

Front

What causes the increase in atomic radius down a group?

Back

The addition of electron shells increases the distance between the nucleus and the outermost electrons.