Question

Nam d residue obtained whn wood is burnt in a limited supply of air.

Answer 1

when wood is burnt, then it produces gases and ash is left after burning wood that is ash is the residue after burning wood in limited air

Answer 2

Charcoal is obtained when wood is burnt in limited supply of oxygen. Charcoal is considered a better fuel than others since it does not produce pollution in a large amount This is why wood is burnt with limited O2. Cheers!