Question

Which statement best describes why electrons are typically not included when determining the mass of an atom?

The charge of a proton cancels the charge of an electron.

The protons and neutrons are much more massive than the electrons.

Electrons have a negative charge.

Electrons are located outside the nucleus

Answer 1

The protons and neutrons are much more massive than the electrons.

Answer 2

The protons and neutrons are much more massive than the electrons.

The electrons are simply too small to really change the mass, so they aren't counted.