Inquiry Question 3: Periodicity

Question 1

Atomic Radius: Down a group

Answer 1

atomic radius increases –> more electrons and protons

valence electrons less strongly attracted to the nucleus as they are further away

Question 2

Atomic Radius: Across a period

Answer 2

atomic radius decreases –> number of protons increase

∴ inward pull of nucleus increases resulting in a smaller radius as each electron is closer to the nucleus

Question 3

First ionisation energy: Down a group

Answer 3

Decreases (easier to remove electron)
Elements bigger with more electrons + electron shells
Larger atomic radius makes it easier to remove an electron
Extra inner shells shield outer shells from the attraction of the nucleus

Question 4

First ionisation energy: Across a period

Answer 4

Increases (harder to remove electron)
Electrons increasing in atomic number = more protons
More charge in nucleus –> increases the pull between the electrons and nucleus
Nucleus larger –> attracts more electrons strongly

Question 5

Electronegativity

Answer 5

Measures the tendency of an atom to attract a pair of electrons
The larger amount of energy levels –> smaller the attraction of the nucleus
Elements containing more electrons = less electronegative as electrons are cancelling out the attraction of nucleus
From left to right across periods –> more electrons in outer shell making outer shell have more energy = attracts electrons strongly