The general formula for an alkane is C_nH_2n+2, where 'n' represents the number of carbon atoms in the molecule.

Here's what it means:

* C_n: This part signifies that there are 'n' carbon atoms in the alkane molecule.

* H_2n+2: This part indicates that the number of hydrogen atoms is twice the number of carbon atoms plus two.

Examples:

* Methane (CH₄): n = 1, so the formula is C₁H₂₍₁₎₊₂ = CH₄

* Ethane (C₂H₆): n = 2, so the formula is C₂H₂₍₂₎₊₂ = C₂H₆

* Propane (C₃H₈): n = 3, so the formula is C₃H₂₍₃₎₊₂ = C₃H₈

This formula applies to all straight-chain and branched-chain alkanes.