Final answer:
Yes, it is the vapors of a substance that typically burn. Organic solvents are flammable due to their evaporating nature, and combustion is a chemical reaction that involves the interaction of vapor and oxygen, resulting in fire and energy release.
Step-by-step explanation:
To answer your question, yes, it is indeed the vapors of a substance that typically burn, not the liquid itself. Many organic solvents are flammable or highly flammable, depending on their volatility. Exceptions exist, such as some chlorinated solvents like dichloromethane and chloroform that are less flammable. When a substance burns, it undergoes a chemical reaction, where the combustible vapor reacts with oxygen in the air to produce fire. This combustion process involves breaking and forming of molecular bonds, releasing energy, and often resulting in new substances like water and carbon dioxide.
In general, the form a substance is in significantly affects how it interacts with its environment and what dangers it may pose. For example, liquid solvents can evaporate and produce harmful vapors. Combustion of these vapors can occur when mixed with air, especially if there is a source of ignition, leading to an explosion or fire.