Which atom has an atomic number of 4

• Sodium

• Beryllium

• Oxygen

• Helium

How many protons does an atom of oxygen have?

• 8

• 6

• 4

• 10

How many electrons does an atom of helium have?

• 7

• 4

• 2

• 9

In which group is chlorine found.

• 4

• 8

• 7

• 1

In which group is magnesium found.

• 5

• 1

• 3

• 2

In which group is Argon found

• 0/8

• 1

• 4

• 3

What is the atomic number of calcium

• 14

• 4

• 20

• 2

Number of electron in Potassium is

• 12

• 15

• 9

• 10

Elements in the periodic table are in the order of their atomic ..........

Element in the same ..... in the periodic table share similar chemical properties.