Question

Question 1 : Commercial form of silicon can be obtained by __________.
Reduction of silicon dioxide with calcium II carbide in an electric furnace
Reduction of silicon dioxide with magnesium II chloride in an electric furnace
Oxidation of Silicon hydroxide with magnesium II hydroxide
Oxidation of silicon hydroxide with carbon in an electric furnace

Question 2 : _________ is used for making crucibles, as a lubricant in heavy machines and as pencil lead.
Tin
Graphite
Lead
Diamond

Question 3 : Tin is obtained by ___________.
Oxidation of oxides of tin with iron
Oxidation of oxides of tin with carbon
Reduction of oxides of tin with carbon
Reduction of oxides of tin with hydrogen

Question 4 : Germanium is obtained by ____________.
Oxidation of germanium dioxide with mercury
Reduction of germanium dioxide with tin
Reduction of germanium dioxide with carbon or hydrogen
The oxidation of germanium dioxide with copper

Answer 1

1. Oxidation of silicon hydroxide with carbon in an electric furnace
2. Graphite

3. Reduction of oxides of tin with carbon
4. Reduction of germanium dioxide with carbon or hydrogen