Bonding Flashcards
When does ionic bonding happen?
When a metal reacts with a non metal - oppositely charges particles
What is ionic bonding?
When the electron is transferred
What is the compound between a metal and non metal called?
An ionic compound
What are the properties of metals?
- They conduct electricity
- They conduct heat
- They are malleable and ductile
- They have high melting and boiling points
What energy keeps ionic bonds together?
Electrostatic force of attraction
What is covalent bonding?
Sharing electrons
Are covalent or ionic bonds stronger?
Ionic
What does covalent bonding involve?
Two non metals
Do covalent bonds have high or low melting points?
Low
How are metals structured?
A lattice of atoms and a sea of free electrons
What do thermochromic things control?
Temperature
What do photochromic things change?
Light
What can hydrogels do?
Absorb water
How big are nano particles?
1x10(-9)m
What properties does silver/silver nitrate have?
Antibacterial properties
How reactive are alkanes?
Not at all
What are the properties of an ionic compound?
- A three dimensional lattice structure (giant ionic structure)
- A high melting point
- They conduct electricity when molten or dissolved in water
- They’re brittle
How are ions in a sodium chloride crystal arranged?
In a cubic lattice - each ion is surrounded by six nearest neighbors of opposite charge
What kind of compound is water?
A covalent compound
Do covalent bonds conduct electricity?
Nein
How strong is the energy within a covalent bond?
Within the bond it is very strong but the molecules attract each other weakly, so they have low boiling points
What melting points do giant covalent compounds have?
High ones as atoms are held together by very strong covalent bonds
Give two examples of giant covalent structures
Diamond and graphite
What are diamond and graphite made out of?
Carbón
What are carbon atoms in diamond connected to?
Four other carbon atoms, meaning that it’s a three dimensional lattice based on a tetrahedral unit cell
What is graphite made of?
Layers of carbon atoms in hexagonal rings - bind between layers are quite weak and allow layers to slide over one and other