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(i) Calculate the number of electrons which will together weigh one gr...

(i) Calculate the number of electrons wh | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

Question:

(i) Calculate the number of electrons which will together weigh one gram.
(ii) Calculate the mass and charge of one mole of electrons.

Answer:

(i) Mass of an electron = 9.1 x 10^-28 g

9.1 x 10^-28 g contains = 1 electron

Therefore 1g contains = 1/9.1 x 10^-28 *1 = 1.098 x 10²⁷ electrons

(ii) We know, one mole of electron = 6.022 x 10²³ electron

Mass of one electron = 9.1 × 10^–28 g

mass of 6.022 x 10²³ electron = 9.1 x 10^-28 x 6.022 x 10²³ = 5.48 x 10^-4 g

Charge on one electron = 1.6 × 10^–19 coulomb

Charge on one mole of electron = (1.6 × 10^–19 C x 6.022 × 10²³)

= 9.63 × 10⁴ C

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Comments

Shahin
2020-04-28 09:45:44

Thanks...

Priya nayak
2019-10-20 10:11:59

Thanks for the solution

Anant
2019-09-20 14:11:39

Mass of e is 9.1 x 10^31 kg

Siddhu
2019-08-11 21:28:30

Mr/Mrs cha,it's not necessary to take the mass of electron in kg only. We know that the mass of electron is 9.1*10^-28g or 9.1*10^-31kg so the solved question is right

GANDHASIRI KIRANKUMAR
2019-08-09 10:23:18

Super

Cha
2019-06-29 20:03:47

Mass of electron should be in kg

Cha
2019-06-29 19:56:04

Mass of a electron is wrong here.It should be 9.1x 10^-31

Sneha
2019-06-20 16:07:26

Thnks alot

Nice
2019-06-14 10:25:01

ððð

Vansh Tyagi
2019-06-12 15:00:32

But mass of electron is 9.1 Ã10(-34)

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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 1: (i) Calculate the number of electrons which will together weigh one gram. (ii) Calculate the mass a....

(i) Calculate the number of electrons wh | Class 11 Chemistry Chapter Structure of Atom, Structure of Atom NCERT Solutions

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