atomic structure

atomic structure

1. neucleus contains protons and neutrons

2. protons

   • +1 charge, relative mass= 1

3. neutrons

   • neutral charge, relative mass = 1

4. electrons

   • -1 charge, relative mass 1
   • electrons= protons
   • shell, 2,8,8

5. atomic number= number of protons in the nucleus of a atom of an element

6. mass number= number of protons + number of neutrons in the nucleus of an atom of an element

7. 35, 17 Cl

   • \[{}_{17}^{35}Cl\]  
   • 35= mass number
   • 17= atomic number
   • Cl= element
   • 35-17= number of neutrons/ 18

8. relative atomic mass

   • example
     • chlorine has two isotopes, 35, 37
       • 75% of 35 and 25% of 37
         • therefore mass of 100 atoms=
           • ( 75 X 35) + (25 X 37) = 3550
             • one atom = (3550/ 100) = 35.5
   • the number of isotopes with there percentage of how much then add all together and dive by 100