Understanding Carbon Content in Petroleum Products

Petroleum products like petrol, kerosene, lubricant oil, and ligroin are all derived from crude oil and are primarily composed of hydrocarbons. Hydrocarbons are molecules made up of hydrogen and carbon atoms.

The main difference between these substances lies in the size and structure of the hydrocarbon molecules they contain. Generally, as you move from lighter petroleum products (like gases and light fuels) to heavier ones (like oils and waxes), the size of the hydrocarbon molecules increases, meaning they have more carbon atoms in their chains or rings.

Comparing Hydrocarbon Composition

Let's look at the typical range of carbon atoms present in the hydrocarbon molecules found in each option:

• Petrol (Gasoline): Typically contains hydrocarbons with chains ranging from about 4 to 12 carbon atoms (C₄ to C₁₂).
• Kerosene: Contains heavier hydrocarbons than petrol, usually with chains ranging from about 10 to 16 carbon atoms (C₁₀ to C₁₆).
• Ligroin: Also known as petroleum naphtha, it's a light distillate often falling between petrol and kerosene. It typically contains hydrocarbons with about 6 to 10 carbon atoms (C₆ to C₁₀).
• Lubricant oil: Composed of much heavier and larger hydrocarbon molecules, often with chains containing 20 to 50 or even more carbon atoms (C₂₀ to C₅₀₊). These molecules are significantly larger than those found in petrol, kerosene, or ligroin.

Determining Maximum Carbon Quantity

Since lubricant oil contains hydrocarbons with the longest carbon chains and largest molecules among the given options, it will have a higher proportion of carbon atoms per molecule compared to the lighter fuels. Therefore, lubricant oil contains the maximum quantity of carbon among petrol, kerosene, ligroin, and lubricant oil.

The amount of carbon in a hydrocarbon is directly related to the number of carbon atoms in its structure. Heavier fractions of petroleum refining contain larger molecules with more carbon atoms.