(a) What are isobars? Give one example. (b) Write any two uses of isotopes

Write two differences between isobars and isotopes.

Isobars- are atoms of different element which have same mass number but different atomic number. For eg.40Ar18, 40K19 As they have different atomic number so properties are different because no. of valence electrons will be different.


Uses of isotopes are as follows:

1.Deuterium is used as a moderator in nuclear reactors to slow down the speed of fast-moving neutrons. 

2. Deuterium and its compounds are used as a "tracer" in the study of mechanism of various chemical and metabolic reactions taking place in the body. 

3. Tritium is used in nuclear fusion reactions. 

4. Copper-64 is used to study genetic diseases affecting copper metabolism. 

5. Iron-59 is used in studies of iron metabolism in the spleen.



Difference between isotopes and isobars are as follows:


1.)Atoms of same element but have different mass number.

2.)They have same number of protons and electrons but different number of neutrons.

3.)Example:-Carbon- 6 12 C and 14 6C .


1.)Atoms of different elements but having same mass number.

2.)They have same number of protons and neutrons but different atomic numbar .

3.) 40 18Ar and 20 40 Ca

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  • Such atoms which have same mass numbers but different atomic numbers are called as isobars. Where, mass no. = mass of protons + mass of neutrons.

  • The isobar atoms have similar mass, means they differ in all the numbers of electron, protons and neutrons, but the aggregate mass of nucleus is same.

  • For example:

Here, we see that Ar has 18 p, 18 e and 22 neutrons, in K 19p, 19e and 21 neutrons, while in Ca 20p, 20e and 20 neutrons. Hence, all the e, p and n are different in the three atoms but the aggregate mass no = 40. Thus, all the three would be called as isobars.

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1. Atoms of those elements which has same mass numbers but different atomic numbers are known as isobars.

examples for isobars

2.  a)Isobars — atoms of different elements having some mass number

   b) Isobars  different chemical properties 

a) Isotopes — atoms of same element having different mass number

b) Isotopes — similar chemical properties.

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