4.3 Distinguishing Between Atoms Answer Key

Question: The number of ___ in the nucleus of an atom is the atomic ___ of that element

Answer: Protons, Number

Question: Because atoms are electrically neutral, the number of protons and ___ in an atom are equal

Answer: Electrons

Question: The total number of ___ and neutrons in an atom is the mass number

Answer: Protons

Question: Atoms of the same element are identical in most respects, but they can differ in the number of ___ in the nucleus

Answer: Neutrons

Question: Atoms that have the same number of protons but different mass numbers are called

Answer: Isotopes

Question: The ___ of an element is the weighted average of the masses of the isotopes of that element

Answer: Atomic mass

Question: The ___ of an element is the weighted average of the masses of the idol toes of that element

Answer: Atomic mass

Question: Each of the three known isotopes of hydrogen has ___ proton(s) in the nucleus

Answer: 1

Question: The most common hydrogen isotope has ___ neutrons

Answer: No

Question: The most common hydrogen isotope has a mass number of ___ and is called hydrogen-1

Answer: 1