Introduction: When we breathe, we extract oxygen from the air, and use that oxygen for metabolism, which is how we convert the food we eat into useable energy to do the things that we do. One of the by-products of metabolism is carbon dioxide; whenever we exhale, we are getting rid of the carbon dioxide that our bodies produce. The main purpose of breathing, therefore, is to provide our bodies with oxygen, and rid our bodies of carbon dioxide. We humans are terrestrial (land-dwelling) mammals, and as such, our lungs are designed to breathe gas. Therefore, the first problem we must overcome to explore the underwater realm is a means to provide breathing gas. However, if this were the only barrier humans must overcome to enter the sea, we would …show more content…
The partial pressure of a particular gas constituent in a gas mixture is a representation of the portion of the total pressure of the gas mixture exerted by the particular constituent. If you add up all the partial pressures of all the different components of a gas mixture, their total would be equal to the total pressure of the mixture. As confusing as this may sound, partial pressures are actually quite easy to calculate: all you need to know is the fraction of each gas constituent in the mixture, and the total pressure of the gas …show more content…
This law says that the pressure of mixed gases is equal to the pressure produced by the individual gas. It can also be explained by saying that the total pressure of a mixture of gases equals the sum of the partial pressures of gases which are part of it. This means that the number of molecules present in the total volume of a gas is proportional to the number of molecules present on each one of the gases which compose it. This way, while the total gas pressure increases as a diver goes deeper into the water, the partial pressure of each gas involved increases as well, and the effects which might cause on the divers body also increases with it. For example, air is a mixture of gases which contains about 80% of nitrogen and 20% of oxygen although it also includes small amounts of other gases as well. According to Dalton's law, the partial pressure exerted by the nitrogen and by the oxygen which make the air will be equal to the total pressure of the air; and they will increase simultaneously. A specific case in which the effects specified by Dalton's law should be seriously considered by divers is regarding nitrogen. Whenever there is an increase of the partial pressure of nitrogen, this would cause a higher nitrogen concentration dissolved in the diver's blood, and this could cause him to suffer a nitrogen narcosis. This, among many other situations which might arise due to the facts stated by