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Calculate the number of atoms in each of the following (i...

Calculate the number of atoms in each of | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

Question:

Calculate the number of atoms in each of the following

(i) 52 moles of Ar

(ii) 52 u of He

(iii) 52 g of He.

Answer:

(i) 1 mole of Ar = 6.022 × 10²³ atoms of Ar

52 mol of Ar = 52 × 6.022 × 10²³ atoms of Ar

= 3.131 × 1025 atoms of Ar

(ii) Atomic mass of He = 4amu

4amu is the mass of He atoms = 1

Therefore 52 amu is the mass of He atoms= ¼*52 = 13 atoms of He

(iii) Gram atomic mass of He = 4g

4g of He contains = 6.022x 10²³ atoms

Therefore 52 g of He contains = 6.022x 10²³ /4 * 52 = 7.83 x 10²⁴ atoms

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Comments

nitish kumar
2019-09-10 08:34:55

thanks sir this question came to our first terminal exam,

Vipul
2019-08-04 16:34:28

Thanks

Anusha
2019-07-31 22:46:11

Thank u for answering in such a way that is really easy to understand.. ð

Chirantan
2019-07-14 20:55:57

Thank You Sir...

Sanchita sharma
2019-06-26 19:04:19

Thank you it is very helpful for me.

Santosh
2019-06-23 00:52:14

Thank you

Rashmi Chaudhary
2019-05-08 18:00:36

Thanks

Rashmi Chaudhary
2019-05-08 18:00:18

Thanks

Rashmi Chaudhary
2019-05-08 17:59:55

Thanks

Minakshi
2019-04-05 18:54:36

Thank you so much

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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 33: Calculate the number of atoms in each of the following (i) 52 moles of Ar ....

Calculate the number of atoms in each of | Class 11 Chemistry Chapter Some Basic Concepts of Chemistry, Some Basic Concepts of Chemistry NCERT Solutions

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