How many electrons would have to be removed from a coin to leave it with charge +1.0 × 10 ^ 16c
Answers
Answered by
0
Answer:
The charge on an electron is
1.6
×
10
−
19
C
. So for part (a) we can determine that the number of electrons would be:
1.0
×
10
−
7
1.6
×
10
−
19
=
6.25
×
10
11
electrons
For part b, we need to know how may electrons are in the penny. The relative atomic mass of copper is 63.546. By definition, 63.546g of copper would contain a number of atoms equal to Avogadro's constant which is
6.02
×
10
23
m
o
l
−
1
.
So in 3.11g there would be the following number of atoms:
3.11
63.546
×
(
6.02
×
10
23
)
=
2.95
×
10
22
atoms
The atomic number of copper is 29, so a neutral copper atom has 29 electrons.
Hence the fraction of electrons that would need to be removed would be:
6.25
×
10
11
29
×
(
2.95
×
10
22
)
=
7.31
×
10
−
13
Similar questions