1. IONS

2. Ions Charged particles which form when an atom (or group of atoms) gains or loses electrons.

3. Ions Charged particles which form when an atom (or group of atoms) gains or loses electrons. Ions don’t have equal number of PROTONS and ELECTRONS

4. Ions Charged particles which form when an atom (or group of atoms) gains or loses electrons. Ions don’t have equal number of PROTONS and ELECTRONS Each ion (or group) is represented by a symbol which shows the charge of the atom

5. Ions Charged particles which form when an atom (or a group of atoms) gains or loses electrons. Ions don’t have equal number of PROTONS and ELECTRONS Each ion (or group) is represented by a symbol which shows the charge of the atom Metals form positively charged ions while non-metals may form negatively charged ions.

6. Ions Charged particles which form when an atom (or a group of atoms) gains or loses electrons. Ions don’t have equal number of PROTONS and ELECTRONS Each ion (or group) is represented by a symbol which shows the charge of the atom Metals form positively charged ions while non-metals may form negatively charged ions. EG. Na+ is a sodium ion. The + means the charge is +1. This means it has LOST one electron.

7. Ions Charged particles which form when an atom (or a group of atoms) gains or loses electrons. Ions don’t have equal number of PROTONS and ELECTRONS Each ion (or group) is represented by a symbol which shows the charge of the atom Metals form positively charged ions while non-metals may form negatively charged ions. EG. Na + is a sodium ion. The + means the charge is +1. This means it has LOST one electron EG. O 2- is an oxide ion. The 2- sign means it has 2 more electrons than protons

8. Ions Cations – positively charged ions that have lost electrons.

9. Ions Cations – positively charged ions that have lost electrons. Anions – negatively charged ions which have gained electrons.

10. Ions CationsAnions SymbolNameSymbolName K+K+ PotassiumCl - Chloride H+H+ HydrogenNO 3 - Nitrate Na + SodiumHCO 3 - Hydrogen Carbonate Li + LithiumCH 3 COO - Ethanoate Fe 2+ Iron (II)OH - Hydroxide Mg 2+ MagnesiumO 2- Oxide Ca 2 +CalciumS2-S2- Cu 2+ Copper (II)O 2- Sulfide Pb 2+ LeadCO 3 2- Carbonate Zn 2+ ZincSO 4 2- Sulfate Al 3+ Aluminium Fe 3+ Iron (III)

11. Questions: 1.The chloride ion has 18 electrons and is charged -1. a)Write the symbol for the chloride ion b)How many protons has the chloride ion got? 2. The magnesium ion has 12 protons and is charged +2 a)Write down its symbol b)Decide how many electrons the magnesium ion has

12. Fill in this table: Name of element SymbolAtomic number Number of electrons Ion(s) formed Number of electrons lost or gained Magnesium Cl-One gained Na11 Cu2+Two lost Oxygen 19 Li+

13. Fill in this table: Name of element SymbolAtomic number Number of electrons in the ion Ion(s) formed Number of electrons lost or gained MagnesiumMg1210Mg 2+ Two lost ChlorineCl1718Cl - One gained SodiumNa1110Na + One lost CopperCu2927Cu 2+ Two lost OxygenO810O 2- Two gained PotassiumK1918K+K+ One lost LithiumLi32Li + One lost