Chapter 4 Vocab

Question 1

Electron

Answer 1

A subatomic particle that has a negative charge.

Question 2

Nucleus

Answer 2

In physical science, an atom’s central region, which is made up of protons and neutrons.

Question 3

Proton

Answer 3

A subatomic particle that has a positive charge and that it is located in the nucleus of an atom; the number of protons in the nucleus is the atomic number, which determines the identity of an element.

Question 4

Neutron

Answer 4

A subatomic particle that has no charge and that is located in the nucleus of an atom.

Question 5

Atomic Number

Answer 5

The number of protons in the nucleus of an atom; the atomic number is the same for all atoms of an element.

Question 6

Isotope

Answer 6

An atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (and thus a different atomic mass)

Question 7

Unified Atomic Mass Unit

Answer 7

A unit of mass that describes the mass of an atom or molecule; it is exactly 1/12 of the mass of a carbon atom with mass number 12.

Question 8

Mole

Answer 8

The SI base unit used to measure that amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12 g of carbon - 12.

Question 9

Orbital

Answer 9

A region in an atom where there is a high possibility of finding electrons.

Question 10

Valence Electron

Answer 10

An electron that is found in the outermost shell of an atom and that determines the atom’s chemical properties.

Question 11

Photon

Answer 11

A unit or quantum of light; a particle of electromagnetic radiation that has zero rest mass and carries a quantum of energy.

Question 12

Mass Number

Answer 12

The sum of the numbers of protons and neutrons in the nucleus of an atom.