What is the atomic number of an element?

• The atomic number is the mass of an atom in atomic mass units.

• The atomic number is the number of neutrons in an atom.

• The atomic number is the number of protons in an atom.

• The atomic number is the total number of electrons in an atom.

How is the mass number defined?

• The mass number is the sum of protons and neutrons in an atom.

• The mass number is the number of protons only in an atom.

• The mass number is the average weight of an atom's isotopes.

• The mass number is the total number of electrons in an atom.

What distinguishes isotopes of the same element?

• The number of protons in the nucleus.

• The atomic mass of the element.

• The number of neutrons in the nucleus.

• The chemical reactivity of the element.

How do you calculate the average atomic mass of an element?

• Average atomic mass = mass of the element in grams per mole

• Average atomic mass = mass of the most abundant isotope

• Average atomic mass = (mass of all isotopes) / number of isotopes

• Average atomic mass = Σ(mass of isotope × relative abundance)

What is the formula to calculate mass number?

• Mass number = Number of protons x Number of neutrons

• Mass number = Number of electrons + Number of neutrons

• Mass number = Number of protons - Number of neutrons

• Mass number = Number of protons + Number of neutrons

How can you determine the number of neutrons in an atom?

• Number of neutrons = Atomic mass number - Atomic weight

• Number of neutrons = Atomic mass number - Atomic number

• Number of neutrons = Atomic number + Atomic mass number

• Number of neutrons = Atomic number x Atomic mass number

If an element has an atomic number of 6, how many protons does it have?

• 8

• 5

• 6

• 7

What is the mass number of an isotope with 8 protons and 10 neutrons?

• 12

• 20

• 18

• 16

How do isotopes of carbon differ from each other?

• Isotopes of carbon differ in their atomic mass due to varying electron counts.

• Isotopes of carbon differ in their chemical reactivity.

• Isotopes of carbon differ in the number of neutrons in their nuclei.

• Isotopes of carbon differ in the number of protons in their nuclei.

If an element has a mass number of 12 and an atomic number of 6, how many neutrons does it have?

• 6

• 10

• 4

• 8