Chapter 8 Assignment Name Show your work if any is required Circle the answer that is the correct one 1 The ancient Greeks developed a concept of matter that stated that all matter was composed of very small indivisible particles called 2 Using a Cathode Ray Tube with deflecting plates J J Thomson discovered a fundamental subatomic particle called a n 3 The fundamental charge of an electron was discovered by A protons B elements C electrons D atom A proton B neutron C electron D ion A J J Thomson B Robert Millikan C Ernest Rutherford D Niels Bohr 4 Rutherford studied the nature of matter by investigating how alpha particles interacted with thin gold foil He discovered that A nearly all of the alpha particles passed through the foil undeflected B some alpha particles were widely deflected and even were scattered backwards by the nuclei of the atoms in the foil C most of the mass of an atom is concentrated in the nucleus D all of the above are true 5 The number of protons in an atom is called the A atomic number B atomic weight C mass number D isotope number 6 Isotopes of an element have A different number of protons but the same number of neutrons B the same number of protons and neutrons C the same number of protons but different number of neutrons D the same atomic weight 7 The atomic weight of an element is the weighted average of its isotope masses in their relative abundances These isotope masses are compared to what atom A Hydrogen 1 B Carbon 12 C Carbon 14 D Oxygen 16 235 8 Uranium U has A 92 protons 143 neutrons and 92 electrons B 235 protons 92 electrons and 143 electrons C 143 protons 235 neutrons and 143 electrons D 143 protons 143 neutrons and 92 electrons B Electrons in a given orbit do not emit radiation C Electrons must leap from orbit to orbit D Electrons can be treated as particles 9 Which of the following statements does NOT describe Bohr s model of the atom A Electrons can be located anywhere within the atom outside of the nucleus 10 Compare the quantum mechanics model of the atom to the Bohr model of the atom A Quantum mechanics considers the wave behavior of the electron while the Bohr model considers the particle nature of the electron B As long as electrons remain in its orbit it emits no radiation C The location of the particle is known in the Bohr model In the quantum mechanics model the electrons position is defined in probability terms D The Bohr model could not be used for larger atoms E All of the above statements are valid