Grade in last test
How confident are you that you are able to work out the formulae of ionic compounds
These are the rules that you need to know.
Group 1 metal ions have a charge of e.g. Na+
Group 2 metal ions have a charge of e.g. Mg2+
Group 3 metal ions have a charge of e.g. Al3+
Group 5 non-metal ions have a charge of e.g. N3-
Group 6 non-metals have a charge of e.g. O2-
Group 7 non-metals ions have a charge of eg Cl-
The sum of the charges on the ions in a compound is always .
Complete then copy into your notes
These are the polyatomic ions that you need to memorise!
Complete then copy into your notes
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
ammonium | arrow_right_alt | CO32- |
carbonate | arrow_right_alt | SO42- |
sulfate | arrow_right_alt | OH- |
hydrogen | arrow_right_alt | NH4+ |
hydroxide | arrow_right_alt | H+ |
Match the ion to to the charge
Sodium (Na+)
Lithium )Li+)
potassium (K+)
Ag+
NH4+
All group 1 metal ions
+1 ion
-1 ion
2+ ion
2- ion
Match the ion to the charge
group II ions
Magneisum (Mg2+)
Calcium (Ca2+)
Cu in CuO
Iron in FeO
2-
-
+
2+
Match the ion to the charge
Chloride (Cl-)
Bromide (Br-)
Iodide (I-)
group (VII) ions
Halide ions
Nitrate (NO3-)
2+
+
-
2-
Match the ion to the charge
Group VI ions
oxide (O2-)
Carbonate (CO32-)
Sulfate (SO42-)
2+
+
-
2-
The charge on transition metal ions is given by the number in the name.
In copper (II) oxide (CuO) the copper ion has a charge of
The iron in iron (II) oxide (FeO) has a charge of
The copper in copper (I) oxide (Cu2O) has a charge of
The charge of iron in iron (III) oxide (Fe2O3) is
Match the formula to the name
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
Copper (II) carbonate | arrow_right_alt | CuS |
Copper (II) sulfide | arrow_right_alt | CuSO₄ |
Copper (II) oxide | arrow_right_alt | CuCO₃ |
Copper (II) sulfate | arrow_right_alt | CuF₂ |
copper (II) fluoride | arrow_right_alt | CuO |
Match the formula to the name
| Draggable item | arrow_right_alt | Corresponding Item |
|---|---|---|
Copper (I) oxide | arrow_right_alt | CuF₂ |
Copper (i) fluoride | arrow_right_alt | CuO |
Copper (II) oxide | arrow_right_alt | Cu2O |
copper (II) fluoride | arrow_right_alt | CuF |
The full name of a compound can be deduced from the formula.
FeCl2
Method we know that the chloride ion is Cl- as chlorine is in group .
The total charge of the negative ions is 2 x -1 =
The total charge of the compound must be
Therefore the total positive charge has to be
This charge is due to one iron ion so the iron ion has to be
The formula is therefore Iron chloride.
Fe2+
The full name of a compound can be deduced from the formula.
FeCl3
Method we know that the chloride ion is Cl- as chlorine is in group .
The total charge of the negative ions is 3 x -1 =
The total charge of the compound must be
Therefore the total positive charge has to be
This charge is due to one iron ion so the iron ion has to be
The formula is therefore Iron chloride.
Fe3+
Match the compound to the correct charge on the iron ion.
FeO
FeN (Hint nitride is N3-)
Fe(NO₃)₂
Fe2O3
Fe(NO3)3
FeCl3
FeCl2
Fe3+ Iron(III)
Fe2+ iron (II)
How confident are you that you are able to work out the formulae of ionic compounds