Question

Write the balanced equation for the reaction for the following statement:
\[{\text{Mg}}\] burns in presence of air.
A.${\text{Mg}}\left( {\text{s}} \right){\text{ + }}{{\text{O}}_{\text{2}}}\left( {\text{g}} \right) \to {\text{Mg}}{{\text{O}}_2}\left( {\text{s}} \right)$
B.${\text{2Mg}}\left( {\text{s}} \right){\text{ + 2O}}\left( {\text{g}} \right) \to 2{\text{MgO}}\left( {\text{s}} \right)$
C.${\text{2Mg}}\left( {\text{s}} \right){\text{ + }}{{\text{O}}_{\text{2}}}\left( {\text{g}} \right) \to {\text{2MgO}}\left( {\text{s}} \right)$
D.${\text{Mg}}\left( {\text{s}} \right){\text{ + }}{{\text{O}}_{\text{2}}}\left( {\text{g}} \right) \to {\text{MgO}}\left( {\text{s}} \right)$

Answer 1

Hint: Magnesium is an element belonging to the second group of the periodic table. Thus, it is an alkaline earth metal and the properties are similar to each other. It is a shiny, silver white solid. It has the symbol \[{\text{Mg}}\] and the atomic number 12.

Complete step by step answer:
Magnesium does not occur naturally in the free state. It occurs naturally in combination with other elements in which it exists in the +2 oxidation state. The free magnesium metal can be produced artificially and is found to be highly reactive.
The free magnesium metal is found to burn with a characteristic brilliant white light.
Magnesium acts as a source of light. When burning in air, magnesium in the ribbon form or the powder form produces a brilliant white flame. This white flame includes strong ultraviolet wavelengths.
The appearance of the white flame is because of the formation of magnesium oxide when magnesium burns in oxygen of air. The word equation can be written as:
${\text{Magnesium(Mg)}} + {\text{Oxygen(}}{{\text{O}}_{\text{2}}}{\text{)}} \to {\text{Magnesiumoxide(MgO)}}$
The corresponding balanced chemical equation can be written as:
${\text{2Mg}}\left( {\text{s}} \right){\text{ + }}{{\text{O}}_{\text{2}}}\left( {\text{g}} \right) \to {\text{2MgO}}\left( {\text{s}} \right)$

So, the correct option is C.

Additional information:
If the burning ribbon is placed in an atmosphere of nitrogen, it will continue to burn producing magnesium nitride.
When the magnesium oxide formed by burning of magnesium ribbon in air is dissolved in water, it gives magnesium hydroxide.
${\text{MgO + }}{{\text{H}}_{\text{2}}}{\text{O}} \to {\text{Mg}}{\left( {{\text{OH}}} \right)_{\text{2}}}$

Note:
-Magnesium oxide is utilized as a refractory material in the linings of furnaces used for the production of iron, steel, glass, non-ferrous metals and cement.
-Along with other magnesium compounds, magnesium oxide is also used in construction, agricultural and chemical industries.
-The magnesium oxide obtained from calcinations is also used for electrical insulating of fire-resistant cables.