Atomic Number and Atomic Mass

What is the atomic number?

• the number of protons
• the number of protons and neutrons
• the number of neutrons
• the number of protons and electrons

What is the mass number?

• the number of protons
• the number of protons and neutrons
• the number of neutrons
• the number of protons and electrons

What is the atomic mass of this nucleus?

• 1

• 3

• 4

• 7

Tags

NGSS.HS-PS1-8

What is the atomic number of this atom?

• 1
• 3
• 4
• 7

Tags

NGSS.MS-PS1-1

What is the mass number of this atom?

• 4

• 5

• 9

• none of the above

Tags

NGSS.MS-PS1-1

Most of the mass of an atom is contained here.

• electron orbitals 
• nucleus
• shells
• atomic #

An atom of argon has 18 protons and 22 neutrons. How many electrons does it have?

• 18
• 22
• 40
• 4

Tags

NGSS.MS-PS1-1

A phosphorus atom has 15 protons and 16 neutrons. What is the mass number?

• 15
• 16
• 31
• 1

What is the mass number and atomic number ?

• Mass number = 7, atomic number = 14

• Mass number = 14, atomic number = 7

Tags

NGSS.MS-PS1-1

What is the atomic mass of Neon?

• 10
• 30
• 10.18
• 20.18