neutrons isotopes isobars isotones - Overview, Structure, Properties & Uses

Neutrons Isotopes Isobars Isotones - Example, Difference, FAQs

Edited By Team Careers360 | Updated on Jun 08, 2022 05:02 PM IST

Isotones:- what are isotones, simply we can define isotones as if two species have the same number of neutrons they are isotones. Isotones definition is “The nuclei having the same number of nucleons are called isotones”. For them, both the atomic number (Z) and mass number are different but have the difference between (A-Z) is the same. Isotones examples are ₃Li⁷ and ₄Be⁸, ₁H³ and ₂He⁴, and ₁₁Ne²³ and ₁₂Mg²⁴.

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Special features of isotopes:
For example ⁵⁸Co.
Difference between isotopes, isobars, and isotones.
Difference between isobars and isotones
But what is isotone in chemistry

Isotopes:- The atoms of an element whose nuclei have the identical number of protons but different numbers of neutrons are called isotopes of that element. In other words, different isotopes of an element have the same atomic number (Z) but a mass number (A). because of the same atomic number, the isotopes of an element have the same place in the periodic table. almost every element has isotopes. krypton has 6 and 10 has 10 isotopes. isotopes of some elements are the following :

Hydrogen: ₁H¹,₁H², ₁H³

Oxygen: ₈O¹⁶,₈ O¹⁷, ₈O¹⁸

Neon: ₁₀Ne²⁰, ₁₀Ne²¹, ₁₀Ne²²

Chlorine: ₁₇Cl³⁵, ₁₇Cl³⁷

Uranium: ₉₂U²³⁵, ₉₂U²³⁸

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element hydrogen has three isotopes, each having atomic number 1 but their mass number are 1 2 and 3.₁H¹ nucleus has one Proton only, ₁H² nucleus has 1 proton and 1 neutron, ₁H³ nucleus has 1 proton and 2 neutrons. These elements are also known as an isotonic element.

Special features of isotopes:

1 All isotopes of an element have the same number of electrons an atom has an equal number of electrons and protons. Therefore, the chemical properties of different isotopes of an element are the same.

2. The mass number( that is, number of nucleons) of different isotopes of an element are different. Ha Hence, their physical properties are not the same.

3. Chemical properties are the same, two isotopes of the same element cannot be separated by any chemical process. To separate them, physical processes based on atomic mass, like gaseous diffusion, are used

4. Among isotopes of the same element, some may be stable and some radioactive. this is so because of the difference in their nuclear structure. For example, ₆C¹² is stable while ₆c¹⁴ is radioactive.

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Isobars: The nuclei have an identical no of nucleons, but different numbers of protons and different numbers of neutrons are called isobars. Their atomic number (Z) is different but the atomic number (A) is the same. Therefore they have different places in periodic number and also differ in chemical properties. Since in isobars, the numbers of fundamentals particles are different, they differ in physical properties also. The nuclei of isobars belong to different elements. Some examples of isobars are ₁H³ and ₂He³, ₆C¹⁴ and ₇N¹⁴, ₈O¹and ₉F¹⁷.

Isomer:- In physics isomer is defined as the atom of an element whose nuclei have the same number of protons and a same number of neutrons but have different energy states. Radioactive decay of these elements is done with different energy states

For example ⁵⁸Co.

The 71-day half-life of lower energy of isomer ⁵⁸Co and the 9-hour half-life of high energy isomer ⁵⁸Co.The lower energy isomer is decay by electron capture and the higher energy isomer is undergoing a gamma decay.

This is the definition of isotope isobar isotone isomer in physics.

Neutron: Chadwick postulated that the rays obtained by bombarding berylium with ɑ- particles are not ?-rays, but are chargeless particles whose mass is roughly equal to that of proton. He called these particles “neutrons” and expressed their emission by the following equation:

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₄Be⁹ + ₂He⁴ ⟶ ₆C¹² + ₀n¹

Beryllium ɑ-particles carbon neutron

The neutron is represented by ₀n¹because its atomic number is zero and atomic mass is 1.

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Difference between isotopes, isobars, and isotones.

Difference between isobars and isotones

Isotopes	Isobars	Isotones
The atoms of an element whose nuclei have the same number of protons but different numbers of neutrons are called isotopes.	The nuclei which have an identical number of nucleons, but different numbers of protons and different numbers of neutrons are called isobars.	The nuclei having identical numbers of neutrons are called isotones.
Their atomic number (Z) is the same but a mass number (A) is the same.	Their atomic number (Z) is different but a mass number (A) is the same.	Their atomic number (Z) and mass number (A) are different, but the value of (A - Z ) is the same.
Almost all the isotpes have identical chemical and physical properties.	Isobars have different physical properties and chemical properties.	Isotones have different physical and chemical properties.
E.g., ₁H¹,₁H², ₁H³	E.g.,₁H³ and ₂He³	E.g., ₃Li⁷ and ₄Be⁸,

But what is isotone in chemistry

isotones definition chemistry:- Isotone means Atoms of two or more elements have the same number of neutrons but have a varying number of protons. Examples for isotones- ₁₇Cl³⁷, ₁₉K³⁹ both have 20 neutrons.

This is the definition of isotones in chemistry

Isomer in chemistry: Two or one element that has the same molecular formula but different physical and chemical properties. There are two types of isomers

Structural isomers
And, Stereoisomers
Structural isomers:- That element have the same molecular formula but have a different structure.

For example Butane and isobutane, both have the same molecular formula (C₄H₁₀) but differ in structure.

Stereoisomerism: The isomers that have the same number of atoms and have the same molecular formula but are different in the orientation of atoms.

? Did you know?

Who discovered isotopes?

In 1913, Frederick soddy discovered isotopes.

Who discovered isobars?

In 1918, Alfred Walter Stewart discovered isobars.

Who discovered isotones?

Physicist K. Guggenheimer discovered isotones.

Who discovered isomers?

In 1823, J.von Liebig discovered isomer.

J.von Liebig discovered isomer

Iso chemistry:- Iso is a Greek word that means the same. It is a prefix that stands for isomer. Iso means one methyl group connected to secondary carbon in organic compounds.
Isodiaphers:- Those atomic species in which the difference between the number of protons and the number of neutrons ( N - Z ) are the same. For example ₉₀Th²³⁴and ₉₂U²³⁸

Thorium, neutrons = 144 Uranium, neutrons = 146

Protons = 90 Protons = 92

Difference between N - Z = 144-90 = 54. N - Z = 146-92 = 54.

Mirror isobar:- The nuclei have an identical no of nucleons, but different numbers of protons and different numbers of neutrons are called isobars. Their atomic number (Z) is different but the atomic number (A) is the same is called isobars but in mirror isobar, the number of protons and neutrons are interchanged.

For example ₁₂Na²³ and ₁₁Mg²³

Both of the elements have the same mass number (A) = 23

And have the different atomic numbers (Z) = 12 and 11

Now neutrons in Na is N₁ = 23-12 = 11

And in Mg neutrons N₂ = 23- 11 = 12

The atomic number of Na = Number of neutrons in Mg = 12

The atomic number of Mg = Number of neutrons in Na = 11

So, ₁₂Na²³ and ₁₁Mg²³ are mirror isobar.

NCERT Physics Notes:

Isosteres:- Isostere meaning in hindi is samvinyasi. The shapes and often electrons present in the valence shell of molecules or ions are known as isosteres. But the term isosteres are accepted in biomedical as bioisosteres. It is usually used in drug design.