Periodic trends

Question 1

ionisation energy

Answer 1

energy required (per mole) to remove an electron from an atom in the gaseous phase

Question 2

first ionisation energy

Answer 2

the energy required to remove the first electron

Question 3

electronegativity

Answer 3

the tendency of an atom in a molecule to attract bonding electrons

Question 4

Atomic radius

Answer 4

the distance from the nucleus to the border of the outer orbital

Question 5

electron affinity

Answer 5

the energy released when an electron is attached to an atom or molecule to form a negative ion (also a description of how likely an atom is to accept an electron)