Write down any qualitative tests for the presence of oxidising agents and reducing agents.

Balance the given chemical equation by hit and trial method:

$\mathrm{Al}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\stackrel{ }{\to }{\mathrm{Al}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)$

 Construct a balanced ionic equation for this reaction, using the two half equations below:

$2{{\mathrm{IO}}_3}^{-}+12{\mathrm{H}}^{+}+10{\mathrm{e}}^{-}\stackrel{ }{\to }{\mathrm{I}}_2+6{\mathrm{H}}_2\mathrm{O}$

$\mathrm{Zn}\stackrel{ }{\to }{\mathrm{Zn}}^{2+}+2{\mathrm{e}}^{-}$

In the given question, state which reactant has been oxidised:

$\mathrm{PbO}+{\mathrm{H}}_2\stackrel{ }{\to }\mathrm{Pb}+{\mathrm{H}}_2\mathrm{O}$

In the given question, state which reactant has been oxidised:

$\mathrm{CO}+{\mathrm{Ag}}_2\mathrm{O}\stackrel{ }{\to }2\mathrm{Ag}+{\mathrm{CO}}_2$

In the given question, state which reactant has been oxidised:

$2\mathrm{Mg}+{\mathrm{CO}}_2\stackrel{ }{\to }2\mathrm{MgO}+\mathrm{C}$