STRUCTURE OF ATOM - lesson 3

An element has the mass number 12 and atomic number 6. The number of neutrons in it is ______.

• 6

• 10

• 12

• 4

If an atom has 10 electrons, how many protons does it have?

• 0

• 1

• 10

• 5

How many electrons are in an atom with an atomic number of 50?

• 5

• 50

• 2

• 10

What is the mass of this atom? ( 1 proton, 1 electron, 0 neutrons )

• 1

• 0

• 2

• 4

An element with mass number of 11 and atomic number of 5 has how many neutrons?

• 11

• 5

• 6

• 15