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3 years ago

The total negative charge on the electrons in 1mol of helium (atomic number 2, molar mass 4) is ________?

Physics

1 answer:

DaniilM [7]3 years ago

4 0

Answer:

$1.92\times 10^5 C$

Explanation:

We are given that

Atomic number=2

We have to find the total negative charge on the electrons in one mole of Helium.

We know that atomic number=Proton number

Proton number=Number of electrons=2

Number of electrons in Helium=2

1 mole of Helium= $6.02\times 10^{23}$ atoms

We know that q=ne

Where n =Number of fundamental units

e=Charge on electron

1 e= $1.6\times 10^{-19}C$

Using the formula

$q=2\times 1.6\times 10^{-19}=3.2\times 10^{-19}C$

Total negative charge in 1 mole= $3.2\times 10^{-19}\times 6.02\times 10^{23}=1.92\times 10^5C$

Hence, the total negative charge on the electrons in 1 mole of Helium= $1.92\times 10^5 C$

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