Question

Differentiate between spontaneous oxidation, rapid oxidation and slow oxidation.

Answer 1

Spontaneous oxidation	Rapid oxidation	Slow oxidation
When a substance without being ignited by a spark begins to burn on its own, it is called spontaneous oxidation.	When a substance reacts with oxygen rapidly to release a large amount of heat and light energy, it is called rapid oxidation.	When a substance reacts with oxygen at a very slow rate, it is called slow oxidation.
Metals like sodium and potassium react with oxygen spontaneously to form their oxides.	Combustible substances like petrol, diesel, and methane react with oxygen rapidly to produce a large amount of heat and light energy.	Rusting is an example of slow oxidation where iron reacts with oxygen to form iron oxide.
$$\begin{gathered} 4\mathrm{Na}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{Na}}_2\mathrm{O}\left(\mathrm{s}\right) \\ \mathrm{Sodium}\mathrm{Oxygen}\mathrm{Sodium}\mathrm{oxide} \\ 4\mathrm{K}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{K}}_2\mathrm{O}\left(\mathrm{s}\right) \\ \mathrm{Potassium}\mathrm{Oxygen}\mathrm{Potassium}\mathrm{oxide} \end{gathered}$$	$$\begin{gathered} {\mathrm{CH}}_4\left(\mathrm{g}\right)+2{\mathrm{O}}_2\left(\mathrm{g}\right)\to {\mathrm{CO}}_2\left(\mathrm{g}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)+\mathrm{heat}+\mathrm{light} \\ \mathrm{Methane}\mathrm{Oxygen}\mathrm{Carbon}\mathrm{dioxide}\mathrm{Water} \end{gathered}$$	$$\begin{gathered} 4\mathrm{Fe}\left(\mathrm{s}\right)+3{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2{\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right) \\ \mathrm{Iron}\mathrm{Oxygen}\mathrm{Iron}\mathrm{oxide} \end{gathered}$$