law of partial pressures
Học thuậtThân thiện
A scientist demonstrates the law of partial pressures using two connected flasks.
Definition
- Noun:
- Law of partial pressures: A scientific law in chemistry and physics stating that in a mixture of non-reacting gases, the total pressure exerted is equal to the sum of the partial pressures of the individual gases. The partial pressure of a specific gas is the pressure that gas would exert if it alone occupied the entire volume of the mixture at the same temperature.
Usage
- The law of partial pressures is fundamental for calculating gas concentrations in mixtures, such as in atmospheric science, respiratory physiology, and industrial gas processes.
- When applying the law of partial pressures, one must ensure the gases do not react chemically with each other.
- Dalton's law of partial pressures simplifies the analysis of gas behavior in complex systems.
Examples
- According to the law of partial pressures, the total pressure inside a scuba tank containing oxygen and nitrogen is the sum of the pressure from the oxygen and the pressure from the nitrogen.
- To find the amount of oxygen in air, scientists use the law of partial pressures by multiplying the total atmospheric pressure by oxygen's fraction of the mixture.
- The law of partial pressures explains why, at high altitudes, the reduced partial pressure of oxygen can lead to hypoxia.
Advanced Usage
- Mathematical Expression: The law of partial pressures is often expressed as Pn, where each P represents the partial pressure of a component gas.
- Relation to Mole Fraction: A common application of the law of partial pressures is that the partial pressure of a gas (Ptotal) multiplied by its mole fraction (Xa = Xtotal.
Variants and Related Words
- Dalton's law: A common synonym for the law of partial pressures, named after the scientist John Dalton who formulated it.
- Partial pressure (n.): The pressure contributed by a single gas component in a mixture, as defined by the law of partial pressures.
- Ideal gas law: A more general gas law; the law of partial pressures can be derived from it for gas mixtures.
Synonyms
- Dalton's law
Related Concepts
- Henry's law: A law related to gas solubility, which uses the law of partial pressures to state that the amount of gas dissolved in a liquid is proportional to its partial pressure above the liquid.
- Gas mixture: A system to which the law of partial pressures directly applies.
- Non-reacting gases: A key condition for the law of partial pressures to be valid.
A scientist demonstrates the law of partial pressures using two connected flasks.
Noun
- (chemistry and physics) law stating that the pressure exerted by a mixture of gases equals the sum of the partial pressures of the gases in the mixture; the pressure of a gas in a mixture equals the pressure it would exert if it occupied the same volume alone at the same temperature