8th Grade ATOM Review 2025

Which scientists used the cathode ray tube in order to study atoms?

• Rutherford

• Thomson

• Dalton

• Bohr

Which subatomic particles are located in the nucleus of an atom? More than one answer may apply.

• protons

• electrons

• neutrons

• valence electrons

Which of the following subatomic particles provide most of the atomic mass of an atom? More than one answer may apply.

• neutron

• electron

• proton

• valence electron

How many protons are located in Titanium?

• 22

• 18

• 26

• 30

Who discovered the nucleus of the atom?

• JJ Thomson

• Ernest Rutherford

• John Dalton

• Bohr

Tags

NGSS.HS-PS1-8

Which of the following discoveries did Bohr contribute to the atomic model?

• The nucleus is extremely dense.

• The atom is mostly empty space.

• The protons and neutrons are located inside the nucleus.

• Electrons orbit the specific paths around the nucleus.

What did Rutherford learn about most of the atom while completing his experiment with the gold foil sheet?

• There are three subatomic particles in an atom.

• Every atom is exactly the same.

• Atoms do not have a nucleus.

• Most of the atom is empty space.

Chromium (24) has 1 protons, 2 electrons, and 3 neutrons.

• Chromium (24) has 24 protons, 24 electrons, and 28 neutrons.

• Chromium (24) has 12 protons, 12 electrons, and 12 neutrons.

• Chromium (24) has 20 protons, 20 electrons, and 24 neutrons.

• Chromium (24) has 18 protons, 18 electrons, and 20 neutrons.

Tags

NGSS.MS-PS1-1

How many electrons can fit into each energy level of an atom?

• 1st level = 2 ; 2nd level = 8 ; 3rd level = 18 ; 4th level = 32

• 1st level = 2 ; 2nd level = 6 ; 3rd level = 10 ; 4th level = 14

• 1st level = 2 ; 2nd level = 8 ; 3rd level = 8 ; 4th level = 18

• 1st level = 2 ; 2nd level = 4 ; 3rd level = 8 ; 4th level = 16

A subatomic particle that has about the same mass as a proton, but with no electrical charge is called ____________.

• proton

• neutron

• electron

• isotope