Question

The total negative charge on the electrons in 1kg of helium (atomic number 2, molar mass 4) is____________.

Answer 1

Answer:

Explanation:

$n = \frac{m}{M}$

$n = \frac{1000}{4}$

         = 250 moles.

    N  = n×6.02×$10^{23}$

        = 1.505×$10^{26}$

Total charge = (1.505×$10^{26}$) × (1.6×$10^{-19}$)

                     = 2.4×$10^{7}$ C.

Answer 2

Answer:

Number of electrons=2

charge of an electron, e=1.6*10^-19

Q=ne     Q=2*1.6*10^-

-19

m=1kg=1000g

n=m/M=1000/4=250

N=nL

N=2*1.6*10^-19*250*6.02*10^23

N=4.8*10^7 C

Explanation: