The table compares the masses of three unknown subatomic particles.

Relative Mass of Particles

Particle Relative Mass

P 1

Q 0.00054

R 0.99

Which particle is most likely present in the nucleus of the atom?

P and R

Explanation:

The nucleus contains almost the entire mass of the atom.

I would expect both P and R to be in the nucleus.

Answer: P and R

Explanation:

An atom is smallest unit of a matter or substance. It consists of three subatomic particles : electrons, protons, neutrons.

Protons and neutrons are located in the center of an atom where most of the mass of an atom is concentrated.

Electrons are located outside the nucleus where they orbit in different energy levels around the nucleus and weigh much less than protons and neutrons.

As particles P and R have relative masses of 1 and 0.99, which are comparable and thus contribute most to the mass and are located in the nucleus.

Thus particle P and R are most likely present in the nucleus of the atom.