Bonding and structure Flashcards
Define Ionic bonding
In ionic bonding electrons are donated to a more electronegative atom, forming a positive and a negative ions.
Ionic structure -
A giant lattice with positive ions surrounded by negative ions and vice versa. Strong electrostatic attraction occurs between ions.
Remember Dot and cross diagrams!
Yeah I remember thx
Define Covalent bonding
Both electrons are shared between atoms.
Define Dative/co-ordinate covalent bond, might wanna give some examples?
A type of covalent bond where both electrons that are shared come from one atom, NH4+; Al2Cl6
Metallic bonding -
Metals form a lattice with positive metallic ions surrounded by delocalized electrons that move freely within this lattice due to overlap of the outermost s-orbitals, there is a strong attraction between the ions and delocalized electrons which results in a higher melting points.
Delocalisation (bullet points)
- The number of delocalized electrons depends on the number of valence (outer) electrons.
- The number of protons also increases therefore the attraction gets greater.
- More delocalized electrons and more positive core mean stronger metallic bond
- Delocalized electrons also called ‘sea of electrons’
Simple molecular structure -
- Has a beginning and an end(‘finite’), has discrete units.
- Molecules held together via intermolecular forces.
- Atoms covalently bonded to each other.
- C60, Ice, I2 etc.
Giant covalent/molecular structure, examples
Polyatomic/Polymolecular structure held together. Properties are determined by the structure.
Diamond, Graphite
Metallic structure -
Closed packed structure, just layers of bonding structure(here I mean metallic bonding, basically, layers of cations surrounded by the sea of electrons)
Check the table in your photos
Check the answers table there too
