In a human nose, the total area of the region that detects our odors is about ¾ in^2. Compare that to the sensory organ of a hunting dog, whose nose has an active area of about 65 cm^2.

Let it be x

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.