Grade 8 Chemistry Quiz: Elements and Atoms

What is the basic unit of matter?

• Molecule

• Proton

• Electron

• Atom

What does the atomic number of an element represent?

• Number of atoms

• Number of protons

• Number of neutrons

• Number of electrons

Which particle has a negative charge?

• Neutron

• Proton

• Nucleus

• Electron

What is an ion?

• A neutral atom

• A molecule with no charge

• An atom with a different number of protons

• An atom or molecule with an electrical charge

What is the mass number of an atom?

• Number of protons plus neutrons

• Number of neutrons

• Number of electrons

• Number of protons

What is a valence electron?

• An electron in the innermost energy level

• An electron in the outermost energy level

• A neutron in the nucleus

• A proton in the nucleus

Tags

NGSS.HS-PS1-1

NGSS.HS-PS1-2

What is an isotope?

• One of several forms of the same element with different numbers of neutrons

• An atom with a different number of protons

• An atom with a different number of electrons

• A molecule with a different number of atoms

What is the nucleus of an atom?

• The outer shell of an atom

• The positively charged, dense center of an atom

• The negatively charged outer layer

• The space where electrons orbit

Tags

NGSS.MS-PS1-1

What does a periodic table organize?

• Atoms based on their mass

• Chemical elements based on their properties

• Chemical reactions

• Molecules based on their size

What happens in a radioactive atom?

• The electrons stop moving

• The protons and neutrons switch places

• The nucleus remains stable

• The nucleus can spontaneously decay and emit particles