Chemistry 2
Ionic Bonding
If it lost an electron it has a positive charge
If it gained an electron it has a negative charge
The element would lose or gain an electron to get a full outer shell
It is now an ion
A Metal loses an electron to a non-metal
Covalent Bonding
The share electrons
Occurs between non-metal atoms
Atoms are unstable - not got a full outer shell
Simple Covalent Molecules
Low melting and boiling points because of their weak forces
Strong covalent bonds within molecules
No overall charge
Don't conduct electricity
Metals have free electrons which means that electricity can flow
Making Salts
Metal Oxide + Acid makes a salt and water
Metal + Acid makes a salt + hydrogen
Test for Hydrogen - Collect the gas in a test tube and pur a lighted plint in the test tube. If you hear a ssqeaky pop it's hydrogen
Electrolysis
Alkali + Acid makes a salt
Metal Carbonate + Acid makes a salt +carbon dioxide and water
"Splitting up using electricity"
Test for CO2 - Put a just extinguished splint in a test tube full of the gas and if it lights up again its CO2
We use an electric current to break down or decompose a substance made of ions.
pH scale - weak/strong acids or alkalis