ISOTOPES AND NUCLEAR CHEMISTRY ISLAND OF STABILITY

LEARNING TARGETS I CAN CALCULATE AVERAGE ATOMIC MASS (DOK 2) I CAN CALCULATE THE NUMBER OF PARTICLES IN THE NUCLEUS OF THE ATOM USING THE ATOMIC MASS OF AN ISOTOPE (DOK 2) I CAN DEFINE WHAT AN ISOTOPE IS (DOK 1) I CAN WRITE OUT ISOTOPIC SYMBOLS (DOK 1) I UNDERSTAND THAT THE AVERAGE ATOMIC MASS ON THE PERIODIC TABLE IS AN AVERAGE OF ALL ISOTOPES OF THAT ELEMENT (DOK 1) I CAN INFER WHICH ISOTOPE IS THE MOST PREVALENT FROM THE AVERAGE ATOMIC MASS OF THAT ELEMENT (DOK 2) I CAN EXPLAIN HOW ELEMENTS ARE CREATED IN STARS BY THE PROCESS OF FUSION (DOK 3) I CAN EXPLAIN THE PROCESS OF FISSION (DOK 3)

ISOTOPES A VARIATION OF AN ELEMENT, THAT DIFFERS BY THE NUMBER OF NEUTRONS. PROTONS CANNOT CHANGE – A PROTON IS LIKE AN ATOMS DNA, ITS WHAT MAKES IT AN ATOM OF A SPECIFIC ELEMENT ELECTRONS ARE SO SMALL – THEIR MASS IS NEGLIGIBLE TO THE MASS OF AN ATOM NEUTRONS ARE THE ONLY THING THAT CAN CHANGE – CHANGE THE MASS OF THE ATOM WHEN AN ATOM VARIES IN THE NUMBER OF NEUTRONS, ITS MASS ALSO VARIES – THESE ARE CALLED ISOTOPES

ISOTOPIC NOTATION HOW DO WE DIFFERENTIATE BETWEEN DIFFERENT ISOTOPES? ISOTOPES CAN BE WRITTEN IN A LONG FORMAT THAT USES THE ELEMENTS NAME AND MASS CARBON – 12 CARBON – 13 CARBON - 14 ISOTOPES CAN BE WRITTEN WITH SYMBOLS JUST LIKE ELEMENTS CAN:

PRACTICE WITH ISOTOPIC NOTATION ElementIsotopic Symbol Mass NumberAtomic Number Number of Protons Number of Electrons Number of Neutrons Carbon – 14 Polonium –

ATOMIC MASS RECALL WHAT ATOMIC MASS IS: AVERAGE ATOMIC MASS IS THE MASS OF ALL THE ISOTOPES OF AN ELEMENT COMBINED IT IS THE MASS GIVEN ON THE PERIODIC TABLE IT IS CALCULATED BY TAKING THE MASS OF EACH ISOTOPE OF AN ELEMENT AND MULTIPLYING EACH ISOTOPES MASS BY ITS ABUNDANCE THEN ADDING ALL THE ISOTOPES TOGETHER. (% OF MASS 1)(MASS 1) + (% OF MASS 2)(MASS 2) + (% OF MASS 3)(MASS 3)….. YOU WOULD DO THIS FOR EACH ISOTOPE OF THE ELEMENT – SOME ELEMENTS HAVE MANY ISOTOPES POLONIUM HAS 25 ISOTOPES AND ALL ARE RADIOACTIVE

AVERAGE ATOMIC MASS PROBLEMS: COPPER HAS TWO ISOTOPES: 69.2% OF ALL COPPER HAS A MASS OF 63 AMU, WHILE 30.8% OF ALL COPPER HAS A MASS OF 65 AMU. WHAT IS COPPER’S AVERAGE ATOMIC MASS?

NUCLEAR CHEMISTRY RADIOACTIVITY – THE PROCESSES BY WHICH UNSTABLE NUCLEI ACHIEVE STABILITY BY RELEASING RADIATION RADIATION – THE PENETRATING RAYS AND PARTICLES EMITTED BY A RADIOACTIVE SOURCE RADIOACTIVE DECAY – THE PROCESS IN WHICH UNSTABLE NUCLEI DISINTEGRATES RADIOISOTOPES – AN ISOTOPE THAT HAS AN UNSTABLE NUCLEUS AND UNDERGOES RADIOACTIVE DECAY

NUCLEAR REACTIONS A REACTION THAT RESULTS IN A DIFFERENT NUCLEUS ALL REACTIONS KNOWN UP TO THIS POINT, HAVE NOT CHANGED THE NUCLEUS LAW OF CONSERVATION OF MASS NUCLEAR REACTIONS DO NOT SEEM TO FOLLOW THIS LAW.

FISSION AND FUSION REACTIONS FISSION NUCLEAR DECAY THAT RESULTS FROM THE NUCLEUS OF AN ATOM SPLITTING IN TO SMALLER PIECES HEAVIER ATOM BECOMES A LIGHTER ATOM THE IS NUCLEAR ENERGY ON EARTH REQUIRES LITTLE TO NO ENERGY (USUALLY) RESULTS IN: FREE FLOATING NEUTRONS AND PHOTONS (ENERGY) FUSION NUCLEAR REACTION THAT RESULTS FROM TWO NUCLEI JOINING TOGETHER TO FORM ONE LARGER NUCLEUS DOES NOT OCCUR ON EARTH IF IT DID, IT WOULD SOLVE OUR ENERGY CRISIS RELEASES GAMMA RADIATION FOR EVERY REACTION THIS IS WHAT WE COULD USE FOR ENERGY REQUIRES TOO MUCH ENERGY TO START THE REACTION POWERS ACTIVE STARS

FISSION AND FUSION FISSION VS FUSION