Chapter 15, Problem 12TE

To determine

Whether the electron or proton contributes more to an atom’s mass and atom’s size.

Answer to Problem 12TE

The proton contributes more to an atom’s mass and electron contributes more to an atom’s size.

Explanation of Solution

The atom’s mass is the addition of all the electron, proton and neutron in that atom. The mass of the electron is nearly negligible with the mass of the proton and neutron. The number of protons is higher than the number of neutrons in an atom, so the proton of an atom contributes more to an atom’s size.

The size of the nucleus is very less compared to the complete size of an atom. The electrons are spread around the nucleus in an atom, so the electrons contribute more to an atom’s size.

Conclusion:

Therefore, the proton contributes more to an atom’s mass and electron contributes more to an atom’s size.