Children: Isotopes
Gold (Au) has a few naturally occurring isotopes, the most common of which is gold-197 (^197Au). This isotope is stable and makes up nearly all naturally occurring gold. Gold-197 has an atomic mass of approximately 196.96657 u. In addition to ^197Au, there are several radioactive isotopes of gold, though they are not found in nature and are typically produced in laboratories or through nuclear reactions.
Hafnium (Hf) is a chemical element with the atomic number 72 and has several isotopes. The isotopes of hafnium are distinguished by the number of neutrons in their nuclei, and they can be either stable or radioactive. Here are the key isotopes of hafnium: ### Stable Isotopes: 1. **Hafnium-174 (Hf-174)**: The most abundant stable isotope, making up about 32.5% of natural hafnium.
Hassium (Hs) is a synthetic element with the atomic number 108. It is a member of the transactinide series of elements and is classified in Group 8 of the periodic table. As of my last knowledge update in October 2023, hassium has a few known isotopes, with all of them being radioactive.
Holmium (Ho) has one stable isotope, holmium-165 (Ho-165), which makes up nearly all naturally occurring holmium. In addition to this stable isotope, holmium has several radioactive isotopes, with varying half-lives. The most notable radioactive isotopes of holmium include: 1. **Holmium-163 (Ho-163)** - This isotope is used in various applications, including neutron capture therapy and as a source of gamma radiation.
Hydrogen has three main isotopes, which vary based on the number of neutrons present in the nucleus: 1. **Protium (^1H)**: This is the most abundant isotope of hydrogen, consisting of one proton and no neutrons. It is represented as \(^1H\) or simply H. 2. **Deuterium (^2H or D)**: This isotope contains one proton and one neutron, giving it a mass number of two.
Indium has two stable isotopes: \(^{113}\text{In}\) and \(^{115}\text{In}\). 1. **\(^{113}\text{In}\)** - This isotope has a natural abundance of about 4.3%. It is a stable isotope, meaning it does not undergo radioactive decay. 2. **\(^{115}\text{In}\)** - This isotope is the most abundant, accounting for about 95.
Iodine has several isotopes, the most notable of which are iodine-127, iodine-129, and iodine-131. 1. **Iodine-127 (¹²⁷I)**: This is the most stable and abundant isotope of iodine, making up about 100% of naturally occurring iodine. It has a half-life that is effectively infinite for practical purposes and is non-radioactive.
Iridium has several isotopes, with the two most stable and naturally occurring ones being: 1. **Iridium-191 (Ir-191)**: This isotope has a half-life of about 19.17 hours and decays to stable osmium-191. It is a product of the decay of heavier elements and is not found in significant amounts in nature.
Iron has several isotopes, which are variants of the element that have the same number of protons but different numbers of neutrons. The most stable and commonly occurring isotopes of iron are: 1. **Iron-54 (\(^{54}Fe\))**: This is the most abundant stable isotope, making up about 5.8% of natural iron.
Krypton (Kr) is a noble gas with atomic number 36. It has several isotopes, which are variants of the element that have the same number of protons but different numbers of neutrons. The most notable isotopes of krypton include: 1. **Krypton-78 (Kr-78)**: This isotope has 42 neutrons and is stable. 2. **Krypton-80 (Kr-80)**: This stable isotope has 44 neutrons.
Lanthanum (La) has a few isotopes, but it has only one stable isotope: lanthanum-138 (¹³⁸La). This isotope accounts for nearly all naturally occurring lanthanum. In addition to the stable isotope, lanthanum has several radioactive isotopes. These isotopes include: 1. **Lanthanum-137 (¹³⁷La)**: A beta-emitting isotope with a half-life of about 6.
Lawrencium (Lr) is a synthetic element with the atomic number 103, and it is part of the actinide series. Due to its instability and short half-life, isotopes of lawrencium are not found naturally and have been produced in laboratories.
Lead has four stable isotopes and several unstable (radioactive) isotopes. The four stable isotopes of lead are: 1. **Lead-204 (\(^{204}\)Pb)**: This isotope has 82 protons and 122 neutrons. It is the least abundant stable isotope of lead. 2. **Lead-206 (\(^{206}\)Pb)**: This isotope has 82 protons and 124 neutrons.
Livermorium (Lv) is a synthetic element with the atomic number 116. It belongs to the group of elements known as the post-transition metals. As of my last knowledge update in October 2021, livermorium has a limited number of known isotopes. The most stable and notable isotopes of livermorium are: 1. **Livermorium-293 (Lv-293)**: This isotope has been produced and has a half-life of approximately 60 milliseconds.
Lutetium (Lu) is a chemical element with the atomic number 71 and is part of the lanthanide series. It has several isotopes, but the most notable ones are as follows: 1. **Lutetium-175 (Lu-175)**: This is the most stable and abundant isotope of lutetium, making up about 97.4% of natural lutetium.
Magnesium has several isotopes, with the most notable being: 1. **Magnesium-24 (²⁴Mg)**: This is the most abundant isotope, making up about 79% of natural magnesium. It has 12 neutrons and is stable. 2. **Magnesium-25 (²⁵Mg)**: This isotope constitutes about 10% of natural magnesium. It has 13 neutrons and is also stable.
Manganese has several isotopes, with the most common being ^55Mn, which is stable. In total, there are 26 known isotopes of manganese, ranging from ^46Mn to ^75Mn. Here are some key points regarding manganese isotopes: 1. **Stable Isotope**: - **^55Mn**: The only stable isotope of manganese, making up nearly all natural manganese found in the environment.
Meitnerium (Mt) is a synthetic element with the atomic number 109 and is classified as a transactinide element in the periodic table. It is named in honor of physicist Lise Meitner. Due to its short half-life and the limited amount produced, there are only a few known isotopes of meitnerium.
Mendelevium (Md) is a synthetic element with the atomic number 101, and it is a member of the actinide series in the periodic table. As of my last update in October 2023, mendelevium has no stable isotopes. The known isotopes of mendelevium are all radioactive, and they have relatively short half-lives.