Calcium carbonate is a chemical compound with the formula CaCO3. It is a common substance found in rocks as the minerals calcite and aragonite (most notably as limestone, which contains both of those minerals) and is the main component of pearls and the shells of marine organisms, snails, and eggs.
An ordinary breath for a 70-kg adult is about 500ml of air. We call this the tidal volume. Since oxygen is 21% by volume of air, then the volume of oxygen inhaled is about 105ml. The density of pure oxygen at sea level is 1.43kg per cubic metre.
There is one thing that everyone who lives and visits Maricopa County has in common. We all breathe air. The average adult takes about 15 breaths per minute, inhaling nearly two gallons of air. With 21,600 breaths per day that equals 2,880 gallons of air each day. Maricopa County Air Quality Department is asking everyone to help keep our air clean and our residents healthy.