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Classification of Elements and Periodicity in Properties
How does atomic radius vary in a period and in a group? How do you exp...

How does atomic radius vary in a period | Class 11 Chemistry Chapter Classification of Elements and Periodicity in Properties, Classification of Elements and Periodicity in Properties NCERT Solutions

Question:

How does atomic radius vary in a period and in a group? How do you explain the variation?

Answer:

Atomic radius of the elements generally decreases from left to the right in a period because on moving from left to right in a period the nuclear charge gradually increases by one unit and one electron is also added in the electron shell. Due to this the electrons get attracted more and more towards the nucleus consequently the atomic radii decrease.

Atomic radius of the elements increases as we move downwords in a group because on moving down a group there is an increase in principal quantum number and thus, increase in the number of electron shells. Therefore the atomic size is expected to increase.

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Comments

RONNIE
2019-09-24 14:54:56

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RONNIE
2019-09-24 14:54:37

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Shaina
2019-09-04 20:24:52

Thnks

Souptik
2019-08-06 20:37:11

This answer helped me truly.

modan
2019-07-28 08:22:33

Thanks.

Sunil Kumar
2019-06-20 20:46:15

Thanks

Abhishek
2019-05-28 19:54:28

Oo yeah

Divyanshi
2019-05-21 12:38:48

This answer really helped me

Spondon Jyoti Dutta
2019-03-05 22:18:44

Thanks

Rajkumar
2018-12-19 11:00:01

Thanks this answer is very helpful..

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Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 10: How does atomic radius vary in a period and in a group? How do you explain the variation?....

How does atomic radius vary in a period | Class 11 Chemistry Chapter Classification of Elements and Periodicity in Properties, Classification of Elements and Periodicity in Properties NCERT Solutions

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