20.5 Energy of Nuclear Reactions and Nuclear Binding Energy

Course Menu
CHECK OUT CHAD'S
PRE-HEALTH PREP
Table of Contents
    Add a header to begin generating the table of contents

    Nuclear reactions release a LARGE amount of energy as mass is converted to energy.

    E = Δmc2

    Δm, the mass defect, must be in kg (1amu = 1.67 × 10-27kg)
    c = 3.0 × 108m/s (speed of light)

    Mass Defect (Δm) – The difference in mass between the products and reactants of a nuclear reaction
    (the products will always weigh less—the mass lost is converted to energy)

    nuclear reaction 01

    Calculate the amount of energy released for the nuclear fission of one uranium-235 atom.

    Isotope/ Particle Mass
    isotope particle 01 235.04393amu
    isotope particle 02 1.00866amu
    isotope particle 03 141.91643amu
    isotope particle 04 90.92345amu

    Nuclear Binding Energy (total vs. per nucleon)

    -The energy that holds the nucleus together
    -56Fe has the highest nuclear binding energy per nucleon and typically the closer in mass you are to 56, the higher the nuclear binding energy per nucleon.

    E = Δmc2

    Δm, the mass defect, must be in kg (1amu = 1.67 × 10-27kg)
    c = 3.0 × 108m/s (speed of light)

    Mass Defect (Δm) – The difference between the nuclear mass and the mass of the constituent nucleons
    A nucleus always weighs less than its constituent nucleons

    CALCULATING NUCLEAR BINDING ENERGY (per nucleon)
    1. Calculate the mass defect (Δm = actual mass – predicted mass)
    2. Convert to kg (6.02 × 1023 amu = 1g or 1amu = 1.66 × 10-27 kg)
    3. Plug into E = Δmc2
    4. Divide by mass number (mass # = number of nucleons)

    Calculate the nucelar binding energy per nucleon for iron-56 and uranium-235

    nuclear binding energy 01
    nuclear binding energy 02
    Nuclide/ Particle Mass
    nuclide particle 01 1.00728amu
    nuclide particle 02 1.00866amu
    nuclide particle 03 235.04393amu
    nuclide particle 04 55.93494amu