Final answer:
The pure form of natural gas is predominantly composed of methane (CH₄), making methane (option D) the correct answer to the question.
Step-by-step explanation:
The main answer to the question of what the pure form of natural gas is can be found by looking at the composition of alkanes. Natural gas is predominantly composed of methane (CH₄), which is the simplest alkane. Butane (C₄H₁₀) is another alkane but is not the primary component of natural gas; it is used in camping stoves and lighters. Methane serves as an excellent fuel due to its ability to burn and produce carbon dioxide and water vapor upon combustion.Among the options provided, methane (option D) is the correct answer because it is the principal component of natural gas. Alkanes such as ethane (C₂H₆) and propane (C₃H₈) can also be present in natural gas but are separated and used in other applications. Methane's role as the main component of natural gas is summarized in various chemical texts both as a component of natural gas and its utilization as a fuel source due to its combustion reaction.In conclusion, methane is the primary component of natural gas in its pure form, making it the correct answer to the question.