KS3 Atomic theory

What does atomic number mean?

• How many neuclei an atom has

• How many neutrons an atom has

• how many protons an atom has

How do you calculate how many neutrons an atom has?

• Atomic number - atomic mass number

• Atomic mass number - atomic number

• Atomic number + atomic mass number

• Atomic mass number + atomic number

How do you calculate how many electrons an atom has?

• Same as mass number

• atomic mass number - atomic number

• Same as number of protons

• Atomic mass number + atomic number

Which of the following are found in the nucleus:

• Protons

• Electrons

• Neutrons

• Orbitals

How many protons does Na have?

 $_{ }^{23}Na$  

• 23

• 12

• 11

• 44

How many neutrons does
 $_{ }^{23}Na$  have?

• 23

• 11

• 12

• 44

How many electrons does
 $_{ }^{23}Na$  have?

• 23

• 11

• 12

• 44

How many electrons does $_{ }^{24}Na$   have?

• 23

• 11

• 13

• 44

How many protons does $_{ }^{24}Na$   have?

• 23

• 11

• 13

• 44

How many neutrons does $_{ }^{24}Na$   have?

• 23

• 11

• 13

• 44