Isotopes

A molecule is a bond of two or more atoms, resulting in a chemically inert compound. The atoms share electrons, filling all outer shells of the incorporated atoms. An atom requires so many electrons per shell, in order to be electrically neutral; the first level, that being the closest to the nucleus, requiring two electrons to be balanced, the second shell filling 6 electrons, 10 in the third shell and increasing exponentially the further away from the nucleus. Each shell can only fit that many electrons, but a shell with fewer electrons in a shell than it takes to fill it (with the exception of an entirely empty shell) makes the atom more prone to bonding with another atom. This is the case with Hydrogen, with only 1 electron in the first shell, but requiring 2 to fill it's first shell; naturally bonds with another hydrogen atom forming H2, a diatomic molecule; or a molecule made up of only two atoms. Conversely, Helium, the second atom on the periodic table, consisting of two electrons in it's first shell, is naturally neutral and is part of the Nobel gases on the periodic table; elements that have a natural fill of their electron shells with just one atom. These elements have a low chemical reactivity and seldom bond with other material. An isotope is an atom of a particular element, wit a different atomic mass than the normal element. It possesses the same number of electrons and protons, but posses a varying number of neutrons in it's nucleus. H1, the most common isotope of Hydrogen, consists of a hydrogen atom that contains one proton and no neutron in the nucleus. Physical properties of isotopes can vary, some even being radioactive while others are inert.

The atomic masses shown on the Periodic Table and listed in chemistry textbooks are "weighted" averages of all the naturally occurring isotopes for the particular element in question. The higher the abundance of a particular isotope, the more that isotope contributes to the overall weighted average - that is, to the Atomic Mass on the Periodic Table. Since hydrogen's atomic mass is 1.00 794 atomic mass units, it is clear that the Hydrogen-1 isotope is the most abundant of the three naturally occurring isotopes of hydrogen: protium, deuterium, and tritium. Protium makes up far more than 99% of any naturally occurring sample of hydrogen with deuterium (1 proton and 1 neutron) making up almost all of the rest. Tritium (1 proton and 2 neutrons) is typically present only in trace amounts.

To determine the average atomic mass, the masses of the individual isotopes and their relative abundances are measured using a mass spectrometer. Then the fractional abundance is multiplied by the measured isotopic mass for each isotope and the products of these multiplications are then added together to give the recorded atomic mass on the Periodic Table.

No. isotopes are radioactive because the ratio of protons to neutrons is not right. As proton # increases, more and more neutrons are needed to maintain nuclear stability. If an atom has too many, or too few neutrons, it will be radioactive. Excess (or deficient) electrons are call ions.

Nucleons are the particles that make up the nucleus of an atom. That means protons and neutrons. The number of nucleons here would be 12 because the 6 protons and 6 neutrons add up to 12 nucleons.

The relationship between atomic mass and relative abundance of isotopes was the mas number is the number of protons and neutrons in a normal atom of the element and tha atomic mass is the actual mass of the atom, measured in grams.

For two isotopes to be of the same element it has to have the same atomic number and a different mass number. This means 3116X and 3216X are the same element.

There is only one abundant isotope of fluorine and that is 19F
Fluorine-19 is the most common isotope, its abundance is classed as 100% because no other Fluorine isotopes exist in significant quantities. It is also the only stable Fluorine isotope.

c.
half-life

Because the structure of their nuclei is unstable: too many or too few neutrons, excess energy causing metastable state, etc. To get more stable they decay, emitting alpha, beta, and/or gamma radiation.

Isotopes of a chemical element have the same number of protons and electrons but a different number of neutrons.
A radioactive isotope is unstable and can emit nuclear radiations.

Yes.......most likely. I can't think of anything to do with Uranium, that isn't radioactive!

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Uranium natural isotopes are not so radioactive compared with other isotopes; but all the isotopes of uranium are radioactive.

This is the deuterium isotope, which has a nucleus of one proton and one neutron, whereas the predominant hydrogen isotope has just a proton. In natural water on earth, which is a compound of hydrogen and oxygen, H2O, there is a small proportion of water made from deuterium instead of normal hydrogen, this is often written as D2O. To make heavy water this compound is extracted, so you don't make the heavy water, you separate it out from natural water.

The half life of actinium (for the natural isotope 227Ac) is 21,773 years.

The isotope is named "carbon-12".

1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5s6 6s2 4f14 5d10 6p2, or more concisely [Xe] 6s2 4f14 5d10 6p2.

Francium occurs naturally, although extremely rare. It can and is made in labs. Although it is considered a naturally occurring element, there is only about one ounce of it in the Earth's crust at any one time. Scientists reproduce it in labs so they can study it, ect. So little is known about Francium now; if we didn't reproduce it in labs we would know next to nothing about it.

Technetium-99 is commonly used in medical imaging procedures, particularly in nuclear medicine scans. It is utilized in bone scans, kidney scans, and cardiac stress tests to help diagnose various medical conditions. Its short half-life and ability to emit gamma radiation make it a useful tracer for tracking the function of organs and tissues in the body.

they are different isotopes of copper 1 has 2 more neutrons than the other

Isotopes of zinc are: Zn-64 and Zn-66 to Zn-72.

92

Carbon-14 has more neutrons in its nucleus than does Carbon-12.

Carbon-14 is an isotope which is created when in our upper atmosphere from exposure to solar radiation. C-14 is a great deal less stable when compared to C-12 relative to the geometry of the particles in the nucleus so C-14 naturally decays by nuclear fission to the more stable isotope.

This all means that C-12 is able to latch onto 2 additional neutrons given the energy to do so, but the result is unstable.

I do not know enough more to go into the details of the geometric issues and I think you'd need to be well versed in this subject to understand the specifics anyway :)

NOTE: Carbon dating uses what we know about CO2 levels in the past and uses the rate of decay of C-14 to predict how old materials which came from photosynthesising plants/trees are. This is based on the fact that carbon dioxide is used in photosynthesis so when the plant/tree died and stopped doing this process the amount of C-14 would decay so we can work out when the plant/tree died.

The isotope of carbon is used to date the ancient fossils. Since every living creature had organic matter and carbon is an integral part of that organic matter, it is conventional to use carbon isotope.