Periodic Trends and Bonding Flashcards
Valency/valence number
Number electron an atom needs to lose, gain/share to achieve octet structure
Valence electrons
Electrons in the outermost energy level
Atomic radius
The distance between the centre of the nucleus to the outermost shell
Ionisation energy
Amount of energy required to remove an electron (from a neutral atom in a gaseous state)
Electron affinity
Amount of energy required to add an electron (to a neutral atom in a gaseous state)
Electronegativity
How strongly atoms attract electrons
Periodicity
The gradual change in physical and chemical properties of elements
Electron Affinity:
Increases from ___ to ___ and from ___ to ___
Increases from left –> right and from bottom –> top
F has the highest electron affinity (top right).
Electronegativity:
Increases from ___ to ___ and from ___ to ___
Increases from left –> right and from bottom –> top
F is the most electronegative (top right).
Ionisation energy:
Increases from ___ to ___ and from ___ to ___
Increases from left –> right and from bottom –> top
F has the highest ionisation energy (top right).
Atomic radius:
Increases from ___ to ___ and from ___ to ___
Increases from right –> left and from top –> bottom
Fr has the largest atomic radius (bottom left).
Reactivity
How violently an atom reacts with another substance’s atoms
Ion
An element with a charge
Isoelectric
Atoms with the same electron configuration = same amount of electrons
Rank these in decreasing ion size:
Neutral, Anion, Cation
Anion
Neutral
Cation
What are the exceptions for Ionisation energy?
- Elements that are equally distant cannot be identified which one has a higher IE.
- Group 2A has higher IE than Group 3A. Group 5A has a higher IE than Group 6A.
What is tiebreaker in electronegativity is both elements are equally distanced from fluorine?
The one that is higher up is more electronegative.
What are the exceptions for Electron Affinity?
- Group 1A has a higher electron affinity Group 2A.
- Group 4A has a higher electron affinity Group 5A.
Properties of Covalent compounds
- Lower melting and boiling points than ionic bonds
- More flexible than ionic compounds
- Not soluble in water
- Doesn’t conduct electricity
Properties of Ionic compounds
- Arranged in crystal lattice structure
- Solids are crystalline at room temperature
- High melting and boiling points
- Brittle
Properties of Metallic compounds
- Shiny
- Conduct electricity
- Conduct heat
- High density
- Malleable and ductile
- High melting point
