Question

When the material $P$ mined from the earth is heated strongly in an insufficient supply of air, if produces a solid fuel $Q$ which consists mainly of carbon. When another material $R$ obtained from trees is heated in an insufficient supply of air, it produces another solid fuel $S$ which also consists mainly of carbon. Name $P,Q,R$ and $S$.

Answer 1

Here, $P$ is coal.

Coal is mined from Earth; on heating gives coke $\left(Q\right)$ which consists of carbon.

Wood $\left(R\right)$, obtained from trees on heating with an insufficient supply of air produces charcoal $\left(S\right)$.