Question

Seminar on topic "Isotopes" .
Please give a structure and important points.

Class 8/9/10.

Answer 1

ISOTOPES -  A Seminar


1. Definition: Elements having the same number Z of protons but different number N of Neutrons .

  Meaning of word: iso-tope: same location (in periodic table) .

2. Examples:  U, Pu (plutonium) ,C, H, KL, Sin, Ra. .... H-1 = Protium. H-2 Deuterium. H-3: Tritium. .

Draw a diagram..of atom nucleus.


3. Notation for writing isotopes,  Meaning . Examples.

4. 80 chemical elements have 253 stable isotopes (naturally found). Also there are around 80 unstable isotopes.  Around 3000 stable/ unstable artificial isotopes are created in nuclear reactors. They are radioactive.

Tin has the maximum number (10) of stable isotopes.  Xenon has 8.


5. A Nuclide is same as an isotope. . But only used in nucleus related contexts.

6. Chemical properties
    In general all isotopes have same properties. Reason is (reaction) properties mainly  depend on electrons in an atom.
But isotopes of Hydrogen and some very large elements behave differently.

7. Stability
   In isotopes number N of neutrons is more than that Z of protons. If the ratio N/Z is greater than 1.3 or 1.4 then it is unstable. 

The repulsions between too many nucleons results in decay of nucleus.  They decay by Beta decay or positron decay.  They get converted into another isotope. Also when they are collided by high speed protons/neutrons/ alpha particles,  nuclear fission happens.

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The instability is like the tensions in a house with some hosts and too many guests.
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8. Atomic mass of an element is calculated as the weighted average of masses of its isotopes multiplied by its proportion in the world.

Majority of natural isotopes have even N and even Z.


9. Uses Applications.

**) Detection of adulteration in food products.
**) Identification of source of meteorites by composition of isotopes.  Eg. Meteorites from mars identified this way.

**) Study of some complicated chemical reaction mechanisms: by Kinetic Isotopic Effect.

**) Identification of elements by (radio) spectroscopy. By identifying frequencies of radiations emitted.

**) To determine concentrations of elements or compounds in a substance/ mixture, by Isotope Dilution Method.

**) Radiocarbon dating of fossils etc.

**) Generating power by Nuclear fusion/ fission.

**) Nuclear bombs

**) To treat cancer by radiation therapy.


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Diagrams show isotopes of Hydrogen. Also a plot between N and Z (on x axis) of all atoms. It also indicates stability.

Answer 2

here is an breif explanation of isotopes by @m@n


Isotopes are atoms that have the equal quantity of protons and electrons, however a different quantity of neutrons. Altering the number of neutrons in an atom does now not trade the aspect. Atoms of elements with special numbers of neutrons are known as "isotopes" of that element.. In phrases of chemistry, we will say that these twins are like isotopes of each different.
☆Atoms and factors are fabricated from protons, neutrons and electrons. The nucleus is product of protons and neutrons, and the electrons surround the nucleus, as proven in the illustration under. The sum of the quantity of protons and the quantity of neutrons is equal to the atomic mass.In a given aspect, the number of neutrons may also be specific from each other, while the number of protons is not. These different versions of the identical detail are known as isotopes. Isotopes are atoms with the identical quantity of protons but that have yet another quantity of neutrons. For the reason that the atomic quantity is the same as the quantity of protons and the atomic mass is the sum of protons and neutrons, we are able to additionally say that isotopes are factors with the identical atomic number however distinctive mass numbers.
☆Let us take a look at an example.

Isotopes of Hydrogen
The three are all isotopes of hydrogen. As you will find, they have got the identical atomic number, or number of protons, but distinct atomic masses
The number of neutrons will also be calculated by means of calculating the difference between the atomic mass and atomic number. We will see that for the isotopes of hydrogen, they have got varying quantity of neutrons. For protium, the number of neutrons is zero; for deuterium, the quantity of neutrons is one; and for tritium, the number of neutrons is two.Going back to our assessment with same twins, we will say that these three isotopes of hydrogen are like same triplets of each different - they are going to appear to be equal outside, however they're exceptional within, and they also have unique names.

☆Types of Isotopes
There are two important types of isotopes, and these are radioactive isotopes and stable isotopes. Steady isotopes have a stable mixture of protons and neutrons, so they've steady nuclei and don't bear decay. These isotopes don't pose detrimental effects to residing things, like radioactive isotopes.

They're frequently useful when performing experiments within the environment and in the field of geochemistry. These isotopes can help examine the chemical composition and age of minerals and different geologic objects. Some examples of stable isotopes are isotopes of carbon, potassium, calcium and vanadium.

Radioactive isotopes have an unstable combination of protons and neutrons, so they have got unstable nuclei. For the reason that these isotopes are unstable, they endure decay, and within the procedure can emit alpha, beta and gamma rays.

Radioactive isotopes may also be priceless in unique industries, such as food, agriculture, archaeology and remedy. For illustration, in the meals enterprise, the meals we devour undergoes a process referred to as meals irradiation, the place it's uncovered to gamma rays. This kills bacteria within the meals. In treatment, radioactive isotopes emit gamma rays to support detect tumors. In archaeology, if an object comprises carbon and we are not sure of its age, the isotope of carbon, carbon-14, is used to check its age with a approach referred to as radiocarbon dating.

☆How do we write an isotope?
Typical nuclear notation shows the chemical image, the mass number and the atomic quantity of the isotope. Example: the isotopes of carbon. The detail is determined by the atomic quantity 6. Carbon-12 is the long-established isotope, with carbon-13 as a different steady isotope which makes up about 1%.

☆applications of isotopes


A couple of applications exist that capitalize on residences of the more than a few isotopes of a given aspect. Isotope separation is a giant technological assignment, specifically with heavy elements reminiscent of uranium or plutonium. Lighter factors reminiscent of lithium, carbon, nitrogen, and oxygen are most commonly separated by way of gasoline diffusion of their compounds akin to CO and NO. The separation of hydrogen and deuterium is exceptional due to the fact it's based on chemical as a substitute than physical homes, for example in the Girdler sulfide system. Uranium isotopes have been separated in bulk via gasoline diffusion, gas centrifugation, laser ionization separation, and through a variety of production mass spectrometry.
Isotopes are ordinarily used to assess the concentration of various elements or substances using the isotope dilution system, whereby identified amounts of isotopically-substituted compounds are mixed with the samples and the isotopic signatures of the resulting mixtures are determined with mass spectrometry.