YEAR 9 CHEMISTRY RECAP

YEAR 9 CHEMISTRY RECAP

1. WHAT ARE THE CHEMICALS MADE OF?

   • ATOMS
     • DESCRIPTIONS OF ATOMS HAVE CHANGED OVER TIME
     • STRUCTURE
       • ELECTRONS
         • NEGATIVELY CHARGED
         • ORBIT THE ATOM
         • REMAIN IN ORBIT AROUND ATOM DUE TO ATTRACTION FOR POSITEVELY CHARGED PROTONS
         • CHANGING THE NUMBER OF E - GIVES THE ATOM A CHARGE - CALLED AN "ION"
         • VERY LOW MASS
       • PROTONS
         • POSITIVE CHARGE
         • MASS OF 1
         • NUMBER OF P'S DEFINES THE ATOMIC NUMBER OF AN ATOM - THIS DEFINES THE TYPE OF ELEMENT
       • NEUTRONS