Atomic Number

An element has an atomic number of 9. How many protons do the atoms contain?

• 9

• 8

• 7

• 6

Tags

NGSS.MS-PS1-1

An element with 20 protons in each atom has an atomic number of:

An element has an atomic number of 2. How many protons do the atoms contain?

Sodium has an atomic number of 11. How many protons does each sodium atom have?

• 33

• 22

• 11

• 0

Argon has an atomic number of 18. How many protons does each Argon atom have?

Tags

NGSS.MS-PS1-1

Which of these statements is INCORRECT?

• The number of protons determines the atomic number.

• The atomic number and number of protons are the same.

• An atomic number of 5 means there are 5 protons.

• The number of neutrons is always the same as the number of protons.

What is the atomic number of this atom?

• 1

• 3

• 4

• 7

Tags

NGSS.MS-PS1-1

The fluorine atom has an atomic number of

• 19

• 9

Tags

NGSS.MS-PS1-1

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 number?

• the number of protons

• the number of protons and neutrons

• the number of neutrons

• the number of atoms