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.
1 About 10,000 quarts (9,464 liters) of air go through your lungs every day. 2  The total surface area of the alveoli is around the size of a tennis court. 3  New babies at rest breathe between 40 and 50 times per minute but by the time they're five years old, their breathing rate decreases to around 25 times per minute.