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    Master this deck with 21 terms through effective study methods.

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    What is an elementary particle?

    Elementary particles are the fundamental building blocks of matter and energy, which cannot be broken down into smaller components. They include quarks, leptons, and gauge bosons, and are the basic constituents of atoms.

    Define a mixed element.

    A mixed element is an element that consists of two or more isotopes with different mass numbers. These isotopes can have varying numbers of neutrons, leading to different physical properties while maintaining the same chemical behavior.

    What is an isotope?

    Isotopes are variants of a chemical element that have the same number of protons but different numbers of neutrons, resulting in different mass numbers. Isotopes can be stable or radioactive.

    What is a nucleon?

    Nucleons are the particles found in the atomic nucleus, specifically protons and neutrons. They are responsible for the mass of the nucleus and play a crucial role in nuclear reactions.

    How can you represent a fluorine atom according to Rutherford's model?

    In Rutherford's model, a fluorine atom is depicted as a small, dense nucleus containing protons and neutrons, surrounded by a cloud of electrons orbiting at various distances, resembling a miniature solar system.

    What are the constituent elementary particles of hydrogen (H)?

    Hydrogen (H) consists of one proton and one electron. The most common isotope, protium, has no neutrons.

    Break down the elementary particles of magnesium-24 (24Mg).

    Magnesium-24 (24Mg) consists of 12 protons, 12 neutrons, and 12 electrons, making it a stable isotope of magnesium.

    Identify the elementary particles in uranium-238 (U-238).

    Uranium-238 (U-238) contains 92 protons, 146 neutrons, and 92 electrons, making it the most common isotope of uranium.

    Why is it unnecessary to include the atomic number when specifying an isotope's symbol?

    The atomic number is implied by the element's symbol, as each element has a unique atomic number. Therefore, specifying the isotope's mass number is sufficient to identify it.

    How did Rutherford determine the existence of the nucleus and electron cloud in atoms?

    Rutherford conducted the gold foil experiment, where he observed that most alpha particles passed through the foil, but some were deflected at large angles. This led him to conclude that atoms have a small, dense nucleus surrounded by a cloud of electrons.

    Explain how energy is generated during the fission of uranium-235 in a nuclear power plant.

    During fission, the nucleus of uranium-235 absorbs a neutron and becomes unstable, splitting into smaller nuclei and releasing a significant amount of energy in the form of heat, which is used to produce steam that drives turbines.

    Calculate the natural abundance of the isotopes of boron, given their masses.

    To calculate the natural abundance of boron-10 (10B) and boron-11 (11B), use the average atomic mass of boron and set up equations based on the masses and relative abundances of the isotopes.

    What is the mass defect in the formation of carbon-12 (12C) from its elementary particles?

    The mass defect is the difference between the mass of the individual nucleons (protons and neutrons) and the mass of the carbon-12 nucleus. This mass is converted into binding energy, which holds the nucleus together.

    How is the energy released from the mass defect of carbon-12 expressed in joules and kilowatt-hours?

    The energy released can be calculated using Einstein's equation E=mc², where 'm' is the mass defect. This energy can then be converted from joules to kilowatt-hours by dividing by 3.6 million.

    What limitations exist in the particle model of atomic structure?

    The particle model fails to explain certain phenomena such as electrical charge at the atomic level, the formation of ions, and the behavior of particles during nuclear reactions, necessitating more advanced models like the nuclear shell model.

    Who developed the nuclear shell model and what does it explain?

    The nuclear shell model was developed by Maria Goeppert Mayer and J. Hans D. Jensen. It explains the arrangement of nucleons in the nucleus and the energy levels associated with their configurations.

    What role do neutrons play in the stability of an atomic nucleus?

    Neutrons contribute to the stability of an atomic nucleus by providing an attractive force that helps to offset the repulsive forces between protons, which are positively charged.

    How do isotopes of the same element differ in their chemical behavior?

    Isotopes of the same element have the same number of protons and electrons, thus they exhibit identical chemical behavior. However, their physical properties, such as mass and stability, can differ significantly.

    What is the significance of Rutherford's gold foil experiment in modern physics?

    Rutherford's gold foil experiment was pivotal in establishing the nuclear model of the atom, leading to the understanding of atomic structure and the development of quantum mechanics.

    How does the concept of binding energy relate to mass defect?

    Binding energy is the energy required to separate nucleons in a nucleus. It is directly related to the mass defect, as the mass lost during nucleon binding is converted into binding energy.

    What are the implications of radioactive isotopes in medicine?

    Radioactive isotopes are used in medical imaging and treatment, such as in PET scans and cancer radiotherapy, due to their ability to emit radiation that can be detected or used to target and destroy cancerous cells.