homework 1:\n1. who found the electron and proposed the \plum pudding\ model of atoms?\n2. who found the…

homework 1:\n1. who found the electron and proposed the \plum pudding\ model of atoms?\n2. who found the positively charged nucleus?\n3. who found evidence of neutrons, uncharged, subatomic particles with a mass approximately the same as that of protons?\n4.what does an atom contain?\n5. a atom is neutral, so it contains the same number of positive and negative charges, so the number of protons ____the number of electrons.\n6. the total number of protons and neutrons in an atom is called its ____.\n7. isotopes—atoms of the same element that differ in mass because they have different numbers of ____, but they are chemically identical because they have the same number of ____.\n8. in bohr’s atomic structure model, each orbit round the nucleus is associated with a definite amount of energy and the orbits are, therefore, are called energy ____or main energy ____.\n9. the closer to the nucleus, the____the energy, the more tightly bound the electron is to the nucleus, and the farther away the nucleus, the ____the energy. an orbit or energy level is designated as k, l, m, n shells\n10. when the electron is in the ____energy level, it is said to be in the ground state.

homework 1:\n1. who found the electron and proposed the \plum pudding\ model of atoms?\n2. who found the positively charged nucleus?\n3. who found evidence of neutrons, uncharged, subatomic particles with a mass approximately the same as that of protons?\n4.what does an atom contain?\n5. a atom is neutral, so it contains the same number of positive and negative charges, so the number of protons ____the number of electrons.\n6. the total number of protons and neutrons in an atom is called its ____.\n7. isotopes—atoms of the same element that differ in mass because they have different numbers of ____, but they are chemically identical because they have the same number of ____.\n8. in bohr’s atomic structure model, each orbit round the nucleus is associated with a definite amount of energy and the orbits are, therefore, are called energy ____or main energy ____.\n9. the closer to the nucleus, the____the energy, the more tightly bound the electron is to the nucleus, and the farther away the nucleus, the ____the energy. an orbit or energy level is designated as k, l, m, n shells\n10. when the electron is in the ____energy level, it is said to be in the ground state.

Answer

Brief Explanations:

  1. J. J. Thomson found the electron and proposed the "plum - pudding" model of atoms. Ernest Rutherford found evidence of the nucleus. James Chadwick discovered neutrons. Eugen Goldstein is credited with the discovery of protons.
  2. An atom contains protons, neutrons, and electrons.
  3. Since an atom is neutral, the number of protons equals the number of electrons.
  4. The total number of protons and neutrons in an atom is called its mass number.
  5. Isotopes are atoms of the same element that differ in mass because they have different numbers of neutrons but the same number of protons.
  6. In Bohr’s atomic structure model, each orbit round the nucleus is associated with a definite amount of energy and the orbits are called energy levels or main energy shells.
  7. The closer to the nucleus, the lower the energy. The farther away from the nucleus, the higher the energy.
  8. When the electron is in the lowest energy level, it is said to be in the ground state.

Answer:

  1. J. J. Thomson (electron and plum - pudding model), Ernest Rutherford (nucleus), James Chadwick (neutrons), Eugen Goldstein (protons)
  2. Protons, neutrons, electrons
  3. equals
  4. mass number
  5. neutrons, protons
  6. levels, shells
  7. lower, higher
  8. lowest