Question

How does the mass of an electron compare to the mass of a proton and a

neutron?
A. The mass of an electron is much greater than the mass of a
proton or a neutron.
B. The mass of an electron is greater than the mass of a proton but
less than the mass of a neutron.
C. The mass of an electron is much less than the mass of a proton or
a neutron.
D. The mass of an electron is greater than the mass of a neutron but
less than the mass of a proton.

Answer 1

C. The mass of an electron is much less than the mass of a proton or

a neutron.

Step-by-step explanation:

When we compare the mass of an electron to that of proton or neutron, the mass of an electron is much less than the mass of a proton or a neutron.

Electrons are negatively charged particles in an atom

Protons are positively charged particles

Neutrons do not carry any charges.

• The relative mass of an electron compared to that of a proton is
  `(1)/(1840)`
• This is a very small value
• Electrons generally have mass of 9.11 x 10⁻³¹kg
• Protons weigh 1.67 x 10⁻²⁷kg

• Neutrons weigh 1.68 x 10⁻²⁷kg

We can see that electrons have very small mass and this is why when calculating the mass of an atom, we use the sum of the number of protons and neutrons.