How is gas produced from petroleum?

The production of gas from petroleum primarily occurs through the process of vaporizing the oil and capturing some of what condenses. When crude oil is heated, it vaporizes and separates into various components based on their boiling points. This process is part of refining, where different hydrocarbons are separated for use in energy products like gasoline and diesel fuel. The lighter fractions, which are gases at room temperature, are collected during this process, resulting in the production of gaseous fuels.

This method is essential in the petrochemical industry, as it allows for the efficient extraction and refinement of various hydrocarbon products, making it a fundamental aspect of how gas is derived from petroleum. The other choices do not accurately describe how gas is derived from petroleum. For instance, burning it in combustion engines involves using the energy in the gas that has already been produced, but it doesn't create gas from petroleum. Chemical reactions in refineries contribute to transforming crude oil into different products but do not specifically describe the process of gas production. Finally, cooling oil to freezing temperatures is impractical for gas production, as it would solidify rather than create a usable gaseous product.