2024-25 First Six Weeks Chemistry Review

A(n) _______ is the name given when atoms (whether identical or different) are joined together by chemical bonds.

• element

• molecule

• compound

• mixture

Tags

NGSS.MS-PS1-1

Valence electrons are -

• only found in Noble gases.

• found in all atoms, but only when there is an ionic charge.

• electrons in an atom's outermost shell.

• the electrons of an atom, regardless of shell.

The atomic number ALWAYS identifies the number of __________ in an atom.

• Neutrons

• Protons

• valence electrons

• electrons

A neutral atom has

• same number of protons and neutrons

• more electrons than protons

• same number of protons and electrons

• more protons than electrons

A neutral atom of Iron - 56 contains:

• 26 electrons, 26 protons, and 30 neutrons

• 26 protons, 26 neutrons and 30 electrons

• 26 electrons, 30 protons, and 26 neutrons

Tags

NGSS.MS-PS1-1

Which of the following is the definition of an isotope?

• An atom with the same number of protons, but different numbers of neutrons.

• An atom with the same number of protons, but different numbers of electrons.

• An atom with the same number of neutrons, but different numbers of protons.

• The average of the masses of the isotopes of an element

Carbon-14 (atomic number 6), the radioactive nuclide used in dating fossils, has

• 6 neutrons

• 8 neutrons

• 12 neutrons

• 14 neutrons

Which of the following identifies the atomic mass of an atom?

• the weighted average of the masses of the isotopes of an element

• total number of protons and neutrons in the nucleus of an atom

• the number of protons in the nucleus of an atom

• the number of protons, neutrons and electrons in the nucleus

What is the correct Bohr model of Lithium (Li)?

• A

• B

• C

• D

Tags

NGSS.MS-PS1-1

What scientist first found that the fundamental or basis of everything was an atom?

• JJ Thomson

• John Dalton

• Democratis

• Ernest Rutherford