Topic 3 & 13 Flashcards
Atomic Radius
The distance from the nucleus to the outermost electron
Ionic Radius
The distance from the nucleus to the outermost electrons in an ion
1st Ionisation energy
The energy required to remove 1 mole of electrons from 1 mole of gaseous atoms
Electron affinity
The energy released when 1 mole of electrons is added to 1 mole of gaseous atoms
Electronegativity
A measure of the attraction am atom has for a shared pair of electrons in a covalent bond
What happens to shielding down a group?
Increases
What happens to shielding across a period?
It stays the same
What happens to effective nuclear charge across a period?
Increases
What happens to effective nuclear charge down a group?
Stays the same
What happens to atomic radius across a period?
Increases as no. of energy levels increase
What happens to atomic radius down a group?
Decreases as nuclear charge increases while shielding stays the same; grater forces of attraction between nucleus and valence electron(s)
Are the ionic radii of cations generally greater or smaller than their atomic radii?
smaller
Are the ionic radii of anions generally greater or smaller than their atomic radii?
greater
What happens to metallic character going across a period?
Decreases -electronegativity values increase due to increase in effective nuclear charge and the same shielding, means greater attraction between nucleus and valence electrons
What happens to metallic character going down a group?
Increases-
electronegativity values decrease due to increase in atomic radius & shielding leading to decrease in electrostatic attraction between nucleus and valence electrons
What happens to melting point down group 1?
Decreases aselectrostatic attraction
