We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Dalton's Law?

Karyn Maier
By
Updated Feb 24, 2024
Our promise to you
AllTheScience is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At AllTheScience, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Dalton's law is a principle used in chemistry to predict the concentration of mixed gases in terms of pressure. Also known as Dalton's law of partial pressure, it states that the sum of exerted pressure of the whole mixture of gases is equal to the sum of all pressures in the mixture. Introduced in the early 1800s by John Dalton, an English chemist and physicist, Dalton’s law applies to ideal gases as an absolute empirical law and not real gases. The reason for this is due to the elastic properties of the molecules involved in the former, as well as low particle volume. However, the margin of error when applied to real gases is generally considered minimal in most cases.

Mathematically, Dalton’s law can be expressed as P(1) + P(2) + …P(n), where P = Pressure. As the law observes, the combined pressure of each gas component in the mixture is equal to the total pressure of each gas in the entire mixture. The measurement to represent pressure is expressed in kilopascal units and written as kPa.

Nearly everyone has observed this phenomenon first-hand at some point, whether formally familiar with Dalton’s law or not. One might even recall the classic science experiment from their school years that involved water being displaced from a glass bottle as it was held under a water-filled trough. The lesson learned was that, although the bottle was emptied of water, it was not actually left empty at all. Instead, it filled up with invisible gas as the water was being displaced. This same effect can be observed when doing something as mundane as washing a glass in a kitchen sink full of water, or watching a young child play with a plastic cup in the bathtub.

In the above scenario, it is possible to determine the amount of pressure exerted by the invisible gas captured in the bottle, namely hydrogen. This is done by referring to a table showing the pressure of water vapor at varying temperatures, since a certain amount of water vapor must be accounted for in the equation. The calculation would be the total amount of pressure less the pressure of water vapor. The result would equal the pressure of the hydrogen gas.

While Dalton’s law primarily serves a purpose in the laboratory, it also has real life applications. For instance, scuba divers are concerned with knowing how air and nitrogen are affected at different pressures at varying depths of water. It is also used to determine the concentration of specific gases in the atmosphere.

AllTheScience is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Karyn Maier
By Karyn Maier , Writer
Contributing articles to AllTheScience is just one of Karyn Maier's many professional pursuits. Based in New York's Catskill Mountain region, Karyn is also a magazine writer, columnist, and author of four books. She specializes in topics related to green living and botanical medicine, drawing from her extensive knowledge to create informative and engaging content for readers.

Discussion Comments

By anon958631 — On Jun 28, 2014

The invisible gas cited above is mostly oxygen and nitrogen. Hydrogen plays such an insignificant part, it should not even be mentioned.

By anon143857 — On Jan 18, 2011

your definition about dalton's law is too short.

Karyn Maier

Karyn Maier

Writer

Contributing articles to AllTheScience is just one of Karyn Maier's many professional pursuits. Based in New York's...
Read more
AllTheScience, in your inbox

Our latest articles, guides, and more, delivered daily.

AllTheScience, in your inbox

Our latest articles, guides, and more, delivered daily.