What is an atom made of up? write their properties

An atom is made up of three subatomic particles

1) electron

2) proton

3) neutron

Explanation:

ELECTRONS

1) electrons are negatively charged

2) electron revolve around the nucleus in different engery levels or shells

3) their mass is equal to that of proton

PROTONS

1) they are positively charged

2) they are present inside nucleus

3) their mass is equal to that of electron

NEUTRONS

1) they carry no charge

2) they are present inside the nucleus

when it's short and dry.