C3: Structure and Bonding Flashcards
Covalent Bonding vs Ionic Bonding
Sharing electrons vs transferring electrons.
Giant Ionic Lattice
A huge 3D network of ions, held together by electrostatic attraction (ionic bonding).
Group 1 Ionic Charge
1+
Group 2 Ionic Charge
2+
Group 3 Ionic Charge
3+
Group 4 Ionic Charge
Group 4 don’t form Ions.
Group 5 Ionic Charge
3-
Group 6 Ionic Charge
2-
Group 7 Ionic Charge
1-
Group 0 Ionic Charge
Group 0 never form ions.
Electrostatic Attraction
The force of attraction between positively and negatively charged ions. Act in all directions.
Giant Ionic Structure Facts.
Held together by strong electrostatic attraction.
Very high melting and boiling points because of this.
What happens when an ionic solid melts and becomes a liquid?
The ions are free to move anywhere in the liquid.
Attracted to oppositely charged electrodes dipped into the liquid.
Therefore, they carry their electrical charge through the liquid.
Conduct Electricity.
Water also separates many ionic solids and allows them to conduct electricity.
Covalent Bonds
The bonds between two atoms that share one or more pairs of electrons.
Example of a Macromolecule.
Diamond.
Each carbon atom forms four covalent bonds with its neighbours.
This results in a rigid giant covalent lattice.
Covalent Bond Facts
Covalent bonds are very strong, so the two atoms it joins are very tightly bonded.
However, their intermolecular forces are very weak. Overcoming them is relatively easy and requires little energy.
Do covalently bonded substances conduct electricity?
No.
Giant Covalent Structures/ Macromolecules
STRONG covalent bonds
High melting and boiling points
Insoluble in water
Hard, do not conduct electricity (except for graphite)
Graphite
> Carbon atoms bond to three other carbon atoms.
Form hexagons which are arranged in giant layers.
Layers can slide over each other easily.
Graphite is soft and slippery- Easily malleable.
The fourth electron in Carbon’s outer shell becomes a DELOCALISED ELECTRON- These allow graphite to conduct electricity.
Fullerenes
Form of the element carbon that can exist as large cage-like structures, based on hexagonal rings of carbon atoms.
Nanoscience
The study of particles that are between 1 and 100 nanometres in size.
How do nanoparticles behave?
Differently to their larger scale counterparts.
