1.1 Periodicity Flashcards
What is covalent radius?
Covalent radius is a measure of the size of an atom.
What is the trend across the PT with covalent radius?
Across the PT, atoms gain more protons in the nucleus making a greater nuclear charge. The outer electrons become more attracted to the nucleus so are pulled closer.
Across the PT, covalent radius decreases.
What is the trend going down the PT with covalent radius?
Going down the PT, more energy levels create a shielding effect. The outer electrons are shielded from the attraction to the nucleus so aren’t pulled in.
Going down a group of the PT, covalent radius increases.
What is ionisation energy?
The energy needed to remove one mole of electrons from one mole of gaseous atoms.
What is the trend across the PT with ionisation energy?
Across the PT, atoms gain more electrons meaning a greater nuclear charge. Electrons become more attracted to the nucleus, so more energy is required to remove them.
Across the PT, ionisation energy increases.
What is the trend going down the PT with ionisation energy?
Going down a group in the PT, more energy levels create a shielding effect. The outer electrons are shielded from the nucleus, so less energy is required to remove them.
Going down a group of the PT, ionisation energy decreases.
What is electronegativity?
Electronegativity is the measure of an atoms attraction for electrons in a bond.
What is the trend going across the PT with electronegativity?
Across the PT, atoms gain more protons in the nucleus meaning a greater nuclear charge. Electrons in a bond become more attracted to the nucleus.
Across the PT, electronegativity increases.
What is the trend going down the PT with electronegativity?
Going down a group in the PT, more energy levels create a shielding effect. Bonding electrons are shielded from the attraction to the nucleus.
Going down a group in the PT, electronegativity decreases.
