2CO2

"2CO₂" refers to two molecules of carbon dioxide. Carbon dioxide (CO₂) is a colorless, odorless gas produced when carbon-containing materials, like fossil fuels, are burned, or during respiration in animals and humans. It plays a key role in Earth's climate by trapping heat in the atmosphere, which helps regulate temperature. In chemical formulas, "2CO₂" indicates that there are two molecules of carbon dioxide involved in a reaction or process. Understanding this helps grasp how emissions from activities like driving and industry contribute to climate change.