Heating is enough
Extracting metals of low reactivity.
A very unreactive metal
Mercury sits low in the reactivity series. Its ore is cinnabar, HgS.
How might mercury be got from its ore?
What this lesson covers
The idea
Metals low in the reactivity series are very unreactive, so their oxides are reduced to the metal by heating alone, after any sulphide ore is first converted to the oxide by heating in air.
A very unreactive metal
Mercury sits low in the reactivity series. Its ore is cinnabar, HgS.
How might mercury be got from its ore?
- By heating
- By dissolving it in water
- By cooling it
From cinnabar to mercury
Press Next step. This is only a picture; a teacher or an industry does this.
Only heat is needed
Metals low in the series are very unreactive, so their oxides can be reduced to the metals by heating alone. A sulphide ore, such as cinnabar (HgS), is first heated in air to make the oxide. Copper from Cu₂S can also be obtained by heating in air.
Metals low in the reactivity series are very unreactive, so their oxides are reduced to the metal by heating alone, after any sulphide ore is first converted to the oxide by heating in air.
Notes
Metals low in the series: heating alone reduces their oxides; sulphide ores are first heated in air to make the oxide.
Check yourself
How are oxides of metals low in the reactivity series reduced to the metals?
Cinnabar, an ore of mercury, is first converted by heating in air into ...
What is the chemical formula of cinnabar?
In 2HgO gives 2Hg + O₂, how many oxygen atoms are on the left side?
Answer: 2
2HgO has 2 × 1 = 2 oxygen atoms, which join to make one O₂ molecule.
- By heating alone — correct. Yes!
- By adding a strong acid. The book says that the oxides of these metals can be reduced to metals by heating alone.
- By electrolysis. Electrolytic reduction is for metals high in the series; for metals low in the series heating alone is enough.
- mercury metal. The metal is obtained from the oxide on further heating.
- mercuric oxide, HgO — correct. Yes!
- mercuric chloride. Chlorine is not involved; heating in air gives the oxide.
- HgO. HgO is mercuric oxide, the product of heating cinnabar in air.
- Hg. Hg is mercury, the metal.
- HgS — correct. Yes!