Periodicity

What is periodicity in chemistry?

Periodicity refers to the recurring trends that are seen in the element properties of the periodic table.

What is the periodic law?

The periodic law states that the properties of elements are a periodic function of their atomic numbers.

Define atomic radius.

Atomic radius is the distance from the nucleus to the outermost shell of an electron.

How does atomic radius change across a period?

Atomic radius decreases across a period from left to right due to increased nuclear charge.

How does atomic radius change down a group?

Atomic radius increases down a group as additional electron shells are added.

What is ionization energy?

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

How does ionization energy change across a period?

Ionization energy generally increases across a period due to increased nuclear charge.

How does ionization energy change down a group?

Ionization energy decreases down a group because increased distance from the nucleus reduces the attractive force on the outer electrons.

Define electronegativity.

Electronegativity is the tendency of an atom to attract electrons in a chemical bond.

How does electronegativity change across a period and down a group?

Electronegativity increases across a period and decreases down a group.

What are the factors that affect ionisation energy?

1) Atomic radius

2) Electron shielding

3) Nuclear charge