Question

Write the names of isotopes of hydrogen. What is the mass ratio of these isotopes?

Short answer

The isotopes are Protium, Deuterium, and Tritium. Mass ratios: Deuterium:Protium is 2:1; Tritium:Protium is 3:1.

Step-by-step solution

Identifying Hydrogen Isotopes

Hydrogen has three naturally occurring isotopes: Protium, Deuterium, and Tritium. Protium is the most common isotope with one proton, Deuterium has one proton and one neutron, and Tritium contains one proton and two neutrons.

Determining Atomic Mass of Isotopes

The atomic mass of Protium is approximately 1 u, Deuterium is about 2 u, and Tritium is approximately 3 u. These mass values reflect the number of protons and neutrons in each isotope.

Calculating Mass Ratios

To find the mass ratios, divide the mass of Deuterium and Tritium by the mass of Protium. Therefore, the mass ratio of Deuterium to Protium is 2:1, and for Tritium to Protium, it is 3:1.

Key concepts

Protium

Hydrogen's simplest and most abundant isotope is Protium. It has only one proton and no neutrons in its nucleus. This gives Protium an atomic mass of approximately 1 atomic mass unit (u). As the most prevalent form of hydrogen, it makes up over 99% of hydrogen atoms found in nature. Because Protium's nucleus lacks neutrons, its behavior and properties are unique compared to the heavier isotopes. This lack of neutrons makes Protium incredibly stable, which is one reason it is so common in the universe. Being simple in structure, Protium serves as a fundamental building block in the study of other hydrogen isotopes.

Deuterium

Deuterium, another isotope of hydrogen, contains one proton and one neutron in its nucleus. This configuration gives Deuterium an atomic mass of approximately 2 atomic mass units (u). Deuterium accounts for a small fraction of Earth's hydrogen, about 0.015%. Despite its rarity, Deuterium is crucial in scientific research and industrial applications. For example:

• Used in heavy water to moderate nuclear reactors.
• Benefits in water ice studies, due to its distinct behavior compared to ordinary water ice.

The presence of a neutron makes Deuterium twice as heavy as Protium, impacting its chemical and physical properties subtly.

Tritium

Tritium is the third naturally occurring isotope of hydrogen, with a unique structure that includes one proton and two neutrons. This arrangement results in an atomic mass of about 3 atomic mass units (u). Unlike Protium and Deuterium, Tritium is radioactive and less stable. It is rare in nature but can be artificially produced. Tritium has applications in various fields:

• Used in self-illuminating devices, like wristwatch dials.
• Employed as a tracer in environmental studies.
• Contributes to nuclear fusion research.

The radioactivity of Tritium distinguishes it from other hydrogen isotopes and determines its specific uses.

Mass Ratio

The mass ratio of hydrogen isotopes provides insight into their relative weights, comparing them to Protium. Considering their atomic masses:

• Protium has a mass of 1 u.
• Deuterium has a mass of 2 u.
• Tritium has a mass of 3 u.

Therefore, the mass ratio of Deuterium to Protium is 2:1, indicating that Deuterium is twice as heavy as Protium. For Tritium to Protium, the mass ratio is 3:1, meaning Tritium is three times as heavy as Protium. Understanding these mass ratios is crucial in fields such as chemistry and physics, where isotopic masses influence experimental results and material behavior.

Atomic Mass

Atomic mass is a critical concept in understanding isotopes. It refers to the average mass of an atom, considering the distribution of its isotopes in nature. In the case of hydrogen isotopes, these masses are discrete, correlating with the number of protons and neutrons in each isotope. For hydrogen:

• Protium's atomic mass is about 1 u, given it lacks neutrons.
• Deuterium's atomic mass is 2 u, due to one extra neutron.
• Tritium's atomic mass is 3 u, with two neutrons present.

The atomic mass helps scientists predict the behavior of a specific isotope or calculate its contribution to the atomic mass of an element in its natural form. Different isotopes of the same element thus influence the average atomic mass found on the periodic table.