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.
What is the difference between breath and breathe? A breath (which rhymes with death) is the air inhaled or exhaled during breathing. To breathe (rhymes with seethe) means to inhale and expel air from the lungs. Writers occasionally confuse the words breath and breathe. The word breath is a noun that denotes the air either inhaled or exhaled during breathing.