Scuba divers breathing air at increased pressure can suffer from nitrogen narcosis—a condition resembling drunkenness—when the partial pressure of nitrogen exceeds about 4 atm. What property of gas-water solutions causes this to happen? How can a diver reverse this effect?

Verified step by step guidance

1. insert step 1> Understand that nitrogen narcosis is related to the solubility of gases in liquids, which is described by Henry's Law.
2. insert step 2> Recall Henry's Law, which states that the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid.
3. insert step 3> Recognize that as a diver descends, the pressure increases, leading to an increase in the partial pressure of nitrogen, which in turn increases its solubility in the diver's blood.
4. insert step 4> Understand that the increased solubility of nitrogen in the blood can affect the central nervous system, causing symptoms similar to drunkenness.
5. insert step 5> To reverse the effects of nitrogen narcosis, a diver should ascend to a shallower depth, reducing the pressure and thus the solubility of nitrogen in the blood.

Key Concepts

Partial Pressure

Partial pressure refers to the pressure exerted by a single component of a gas mixture. In the context of scuba diving, as a diver descends, the total pressure increases, which in turn raises the partial pressure of nitrogen in the air they breathe. When the partial pressure of nitrogen exceeds a certain threshold (around 4 atm), it can lead to nitrogen narcosis, affecting the diver's cognitive functions.

Gas Solubility in Liquids

The solubility of gases in liquids is influenced by factors such as temperature and pressure, described by Henry's Law. As the pressure increases, more gas can dissolve in the liquid (in this case, blood). For divers, the increased partial pressure of nitrogen leads to higher nitrogen solubility in their bloodstream, which can result in physiological effects like nitrogen narcosis when the concentration becomes too high.

Decompression and Ascent

To reverse the effects of nitrogen narcosis, divers must ascend slowly to reduce the pressure around them. This process, known as decompression, allows dissolved nitrogen to be released safely from the bloodstream. Rapid ascent can lead to decompression sickness, or 'the bends,' so controlled ascent is crucial for safely managing the nitrogen levels in the body.