Exploring Atomic Number, Mass Number, and Isotopes

What is the atomic number of an element?

• The total number of protons and neutrons

• The number of protons in the nucleus

• The number of neutrons in the nucleus

• The average mass of the element

If an element has 16 protons, what is its atomic number?

• 16.01

• 8

• 16

• 32

Tags

NGSS.MS-PS1-1

What does the mass number of an element represent?

• The number of neutrons

• The number of protons

• The average mass of the element

• The total number of protons and neutrons

Which of the following is true about the mass number?

• It is the same as the atomic mass

• It represents the number of electrons

• It can be a decimal

• It is always a whole number

In atomic notation, what does the subscript represent?

• Mass number

• Atomic number

• Number of neutrons

• Number of electrons

How many neutrons are in an isotope of silicon with a mass number of 29?

• 15

• 29

• 43

• 14

Which isotope of hydrogen has one neutron?

• Hydrogen-2

• Hydrogen-1

• Hydrogen-4

• Hydrogen-3

What is the mass number of an isotope of cobalt with 27 protons and 33 neutrons?

• 33

• 27

• 61

• 60

How many electrons does a neutral neon atom have?

• 14

• 12

• 10

• 8

Tags

NGSS.MS-PS1-1

If a sodium atom has 11 protons and 10 electrons, what is its charge?

• Neutral

• Positive

• Cannot be determined

• Negative