Atomic Structure (Electron, neutrons, protonx)

Review from Science 10
Atoms are made up of 3 types of particles electrons , protons  and neutrons .  
These particles have different properties.  

• Electrons are tiny, very light particles that have a negative electrical charge (-).  
• Protons are much larger and heavier than electrons and have the opposite charge, protons have a positive charge.  
•  Neutrons are large and heavy like protons, however neutrons have no electrical charge.  

Each atom is made up of a combination of these particles. 

protons and neutrons form the nucleus and they are surrounded by the electron

*atomic number is the number of protons
*atomic mass is the number of protons and neutrons

Eg.  Helium
 It has 2 protons and 2 neutrons so its atomic number is 2 and its atomic mass is 4