Question

What do you observe when burning magnesium is lowered in a jar of ${\mathrm{SO}}_2$ ?

Answer 1

• When burning magnesium is lowered in a jar of ${\mathrm{SO}}_2$, magnesium continues to burn and a yellow residue is formed which is sulphur.
• The reaction involved is-
• $\underset{\mathrm{Magnesium}}{2\mathrm{Mg}\left(\mathrm{s}\right)}+\underset{\mathrm{Sulphur}\mathrm{dioxide}}{{\mathrm{SO}}_2\left(\mathrm{g}\right)}\to \underset{\mathrm{Magnesium}\mathrm{oxide}}{2\mathrm{MgO}\left(\mathrm{s}\right)}+\underset{\mathrm{Sulphur}}{\mathrm{S}\left(\mathrm{s}\right)}$
• The above reaction is a type of exothermic reaction because a large amount of heat evolved during this reaction.