IONS

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

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

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

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.

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.

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. O2- is an oxide ion. The 2- sign means it has 2 more electrons than protons

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

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

Ions• Cations Anions

Symbol Name Symbol Name

K+ Potassium Cl- Chloride

H+ Hydrogen NO3- Nitrate

Na+ Sodium HCO3- Hydrogen

Carbonate

Li+ Lithium CH3COO- Ethanoate

Fe2+ Iron (II) OH- Hydroxide

Mg2+ Magnesium O2- Oxide

Ca2+ Calcium S2-

Cu2+ Copper (II) O2- Sulfide

Pb2+ Lead CO32- Carbonate

Zn2+ Zinc SO42- Sulfate

Al3+ Aluminium

Fe3+ Iron (III)

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

c) Write down its symbol

d) Decide how many electrons the magnesium ion has

Fill in this table:

Name of element

Symbol Atomic number

Number of electrons

Ion(s) formed

Number of electrons lost or gained

Magnesium

Cl- One gained

Na 11

Cu2+ Two lost

Oxygen

19

Li+

Fill in this table:

Name of element

Symbol Atomic number

Number of electrons in the ion

Ion(s) formed

Number of electrons lost or gained

Magnesium

Mg 12 10 Mg2+ Two lost

Chlorine Cl 17 18 Cl- One gained

Sodium Na 11 10 Na+ One lost

Copper Cu 29 27 Cu2+ Two lost

Oxygen O 8 10 O2- Two gained

Potassium K 19 18 K+ One lost

Lithium Li 3 2 Li+ One lost