Ionization Energy Trends and Exceptions

The video tutorial explains how the first ionization energy varies across a period, focusing on period 2. It highlights the general trend of increasing ionization energy due to increased nuclear charge and decreased atomic radius. Exceptions to this trend, such as boron and oxygen, are explained through subshell configurations and electron repulsion. The video also compares these trends with period 3, noting similar patterns and exceptions.

What is the general trend of first ionization energy as you move across a period?

• It decreases.

• It remains constant.

• It increases.

• It fluctuates randomly.

Which factor contributes to the increase in first ionization energy across a period?

• Decrease in nuclear charge

• Increase in atomic radius

• Decrease in electron shielding

• Increase in nuclear charge

Why does the atomic radius decrease across a period?

• Due to increased electron shielding

• Due to increased nuclear charge

• Due to decreased nuclear charge

• Due to increased atomic mass

Which elements in period 2 do not follow the general trend of increasing ionization energy?

• Fluorine and Neon

• Boron and Oxygen

• Lithium and Beryllium

• Carbon and Nitrogen

What is the reason for boron's lower ionization energy compared to beryllium?

• Boron has more electron shielding.

• Boron has a higher atomic number.

• Boron has a lower nuclear charge.

• Boron’s outer electron is in a higher energy subshell.

In the case of oxygen, why is its first ionization energy lower than nitrogen's?

• Oxygen has more electron shielding.

• Oxygen has paired electrons that repel each other.

• Oxygen's electrons are in a higher energy level.

• Oxygen has fewer protons.

What is the similarity between the trends in periods 2 and 3 regarding ionization energy?

• Both show a decrease at the same points.

• Both have exceptions at the same elements.

• Both have similar exceptions explained by subshell configurations.

• Both show a constant increase.

Which elements in period 3 show a decrease in ionization energy similar to boron and oxygen in period 2?

• Sulfur and Chlorine

• Silicon and Phosphorus

• Magnesium and Aluminium

• Sodium and Magnesium

What is the main reason for the decrease in ionization energy from magnesium to aluminium?

• Aluminium has more electron shielding.

• Aluminium's outer electron is in a higher energy subshell.

• Aluminium has a lower atomic number.

• Aluminium has a larger atomic radius.

How does the electron configuration affect the ionization energy trend in period 3?

• It results in similar exceptions as in period 2.

• It has no effect.

• It leads to random fluctuations.

• It causes a constant increase.