What are the isotopes of the first 20 elements?

What are the isotopes of the first 20 elements?

Isotopes (Stable) of the elements

What isotopes are in helium?

… stable isotopes of helium are helium-3 (or 3He), with two protons and one neutron, and helium-4 (or 4He), with two protons and two neutrons.

How many isotopes of helium are there?

Element “Helium” has two stable isotopes (3He and 4He) and six radioactive ones (5He, 6He, 7He, 8He, 9He, and 10He).

What are the 3 isotopes of helium?

List of isotopes.

Which of the elements have isotopes?

Every element has its own number of isotopes. The addition of even one neutron can dramatically change an isotope’s properties. Carbon-12 is stable, meaning it never undergoes radioactive decay.

Is helium-4 an isotope?

Helium-4 atom is the stable isotope of helium with relative atomic mass 4.002603. The most abundant (99.99 atom percent) isotope of naturally occurring helium. It contains an alpha-particle.

What is the most common isotope of helium?

Helium-4
Helium-4 also exists on the Moon and—as on Earth—it is the most abundant helium isotope.

Which is the most common isotope of helium?

What is the isotopic symbol of helium?

He
Helium-4 atom is the stable isotope of helium with relative atomic mass 4.002603. The most abundant (99.99 atom percent) isotope of naturally occurring helium. It contains an alpha-particle….4.3Related Element.

What element can be formed when helium-3 and helium-4 are fused?

Once helium-4 builds up, reactions with helium-3 can lead to the production of still-heavier elements, including beryllium-7, beryllium-8, lithium-7, and boron-8, if the temperature is greater than about 10,000,000 K. The stages of stellar evolution are the result of compositional changes over very long periods.

The most widely studied heavy helium isotope is helium-8. This isotope, as well as helium-6, is thought to consist of a normal helium-4 nucleus surrounded by a neutron “halo” (containing two neutrons in 6

What is the half life of heavier helium isotopes?

Heavier helium isotopes. Although all heavier helium isotopes decay with a half-life of less than one second, researchers have created new isotopes through particle accelerator collisions to create unusual atomic nuclei for elements such as helium, lithium and nitrogen.

What is the isotope ratio of helium in the Local Interstellar Cloud?

In the Local Interstellar Cloud, the proportion of 3 is (1.62 ± 0.29) × 10−4, which is 121 ± 22 times higher than that of atmospheric helium. Rocks from the Earth’s crust have isotope ratios varying by as much as a factor of ten; this is used in geology to investigate the origin of rocks and the composition of the Earth’s mantle.

What are the first 20 elements in the periodic table?

These are the first 20 elements, listed in order: 1 H – Hydrogen 2 He – Helium 3 Li – Lithium 4 Be – Beryllium 5 B – Boron 6 C – Carbon 7 N – Nitrogen 8 O – Oxygen 9 F – Fluorine 10 Ne – Neon 更多结果…