The Periodic Table: Atomic Radius, Ionization Energy, and Electronegativity

What is the periodic table of elements?

A systematic arrangement of elements that reveals patterns about how nature operates.

Who created the periodic table that is widely accepted today?

Dmitri Mendeleev.

What are the two main arrangements in the periodic table?

Rows called periods and columns called groups.

Why do elements in the same group behave similarly?

They have the same number of valence electrons.

What happens to atomic radius as you move down the periodic table?

Atomic radius increases because additional electron shells are added.

What happens to atomic radius as you move to the right on the periodic table?

Atomic radius decreases due to increased electromagnetic attraction from more protons.

What is ionization energy?

The energy required to remove an electron from an atom.

How does the ionization energy trend compare to atomic radius?

Ionization energy increases as atomic radius decreases.

Why is francium easy to ionize?

It has a large atomic size with its valence electron far from the nucleus.

What is the trend for successive ionization energies?

Each successive ionization energy is greater than the last.

What is electron affinity?

The amount of energy an atom releases when it gains an electron.

How does electron affinity change across the periodic table?

It typically increases from left to right.

Which element has the highest electron affinity?

Fluorine.

What does electronegativity measure?

The ability of an atom to hold onto its electrons tightly.

How does electronegativity trend across the periodic table?

Electronegativity increases from left to right.

What is a notable exception to the ionization energy trend?

Oxygen has lower ionization energy than nitrogen despite having more protons, due to orbital symmetry.

What is the significance of full outermost shells in chemistry?

Atoms prefer to have their outermost shells full, contributing to their stability.