Carbon dioxide (chemical formula CO 2): a colorless gas with a density about 60% higher than that of dry air. Carbon dioxide consists of a carbon atom covalently double bonded to two oxygen atoms. It occurs naturally in Earth’s atmosphere as a trace gas.
Air bubble that surfaces in a liquid.
gas holder, or gasometer, is a large container in which natural gas or town gas is stored near atmospheric pressure at ambient temperatures.
Carbon monoxide (CO): a colorless, odorless, and tasteless flammable gas that is slightly less dense than air. It is toxic to animals that use hemoglobin as an oxygen carrier (both invertebrate and vertebrate) when encountered in concentrations above about 35 ppm, although it is also produced in normal animal metabolism in low quantities, and is thought to have some normal biological functions.