Question

What happens when butane is burnt in air? Write the chemical equation for the reaction. Differentiate between the flames obtained when butane and butyne both are burnt in air in similar conditions.

Hint:

Butanes generally burn with a blue, non-luminous flame (complete combustion), while alkynes like butyne burn with a yellowish, luminous flame (incomplete combustion).

Answer 1

Reaction of Butane Burning in Air: When butane (\( C_4H_{10} \)) is burned in air, it reacts with oxygen to form carbon dioxide and water: \[ 2 C_4H_{10} + 13 O_2 \rightarrow 8 CO_2 + 10 H_2O \] This is a complete combustion reaction. 
Difference Between the Flames of Butane and Butyne:
Butane (C\(_4\)H\(_10\)): When butane burns in air, it produces a clean, blue flame due to complete combustion, resulting in carbon dioxide and water.
Butyne (C\(_4\)H\(_6\)): When butyne burns, the flame is generally yellowish and smoky due to incomplete combustion, producing carbon monoxide and carbon dioxide along with water.