Atomic Structure

• What is an atom?

  The smallest part of a chemical element
• How can an atom be compared to LEGO blocks?

  Atoms are like tiny LEGO blocks of matter
• What is the charge of protons, neutrons, and electrons?

  They have different charges
• What are the three main particles that make up an atom?

  Protons, neutrons, and electrons
• What happens when the charges of particles in an atom balance?

  The atom becomes neutral
• What is the state of an atom when it is neutral?

  It has balanced charges
• What are the key limitations of the Bohr atomic model?

  • Cannot explain the behavior of multi-electron atoms
  • Does not account for electron spin and magnetic properties
  • Cannot explain the full spectrum of atomic emissions
  • Superseded by the more accurate quantum mechanical model
• What is the name of the atomic model shown in the image?

  Bohr atomic model of a nitrogen atom
• What are the three main subatomic particles shown in the Bohr atomic model?

  Electron, proton, and neutron
• How does the Bohr model differ from the earlier Rutherford model of the atom?

  The Bohr model introduces the concept of discrete electron energy levels, while the Rutherford model had electrons orbiting the nucleus in a continuous fashion
• What charge do electrons carry?

  Negative (-) charge
• How does the Bohr model explain the stability of atoms?

  • Electrons can only occupy certain discrete energy levels
  • Electrons do not emit energy when in these stable energy levels
  • This explains why atoms are stable and do not continuously emit radiation
• Describe the arrangement of particles in a nitrogen atom.

  • Protons (red/green) and neutrons (green) in the nucleus
  • Electrons (blue) orbiting around the nucleus
• What is the name of the atomic model shown in the image?

  Bohr atomic model of a nitrogen atom
• How does the Bohr model explain the stability of atoms?

  • Electrons can only occupy certain discrete energy levels
  • Electrons do not emit energy when in these stable energy levels
  • This explains why atoms are stable and do not continuously emit radiation
• How does the Bohr model differ from the earlier Rutherford model of the atom?

  The Bohr model introduces the concept of discrete electron energy levels, while the Rutherford model had electrons orbiting the nucleus in a continuous fashion
• What are the key limitations of the Bohr atomic model?

  • Cannot explain the behavior of multi-electron atoms
  • Does not account for electron spin and magnetic properties
  • Cannot explain the full spectrum of atomic emissions
  • Superseded by the more accurate quantum mechanical model
• What is the role of the electron orbits in the Bohr atomic model?

  • The electron orbits represent the allowed energy levels for the electrons in the atom
  • Electrons can only occupy specific discrete energy levels, not any arbitrary energy
• How do electrons move in relation to the nucleus?

  They orbit in shells around the nucleus
• What are the two main regions of an atom?

  Nucleus and electron shells
• What is located at the center of an atom?

  The nucleus
• What particles are found in the nucleus of an atom?

  Protons and neutrons
• What charge do protons have?

  Positive charge
• What are the basic components of all elements?

  • Protons
  • Neutrons
  • Electrons
• What is the approximate size of an atom?

  • About 0.1 nanometers (nm)
• What are the three main components of an atom?

  • Nucleus
  • Electron
  • Atom
• How does Schrödinger's quantum model differ from Bohr's model?

  Schrödinger stated that electrons do not move in set paths around the nucleus, but in clouds of probability called orbitals
• How are electrons arranged around the nucleus in an atom?

  Electrons orbit the nucleus in circular paths or shells.
• How do the sizes of the nucleus and the atom compare?

  • The nucleus is much smaller than the overall size of the atom.
  • The atom is mostly empty space with the nucleus at the center.
• How small is an atom compared to dust?

  Much smaller than the smallest speck of dust
• What is the name of the central part of an atom?

  Nucleus
• How do the numbers of protons, neutrons, and electrons vary among elements?

  They differ between different elements
• What charge do electrons have?

  Negative charge
• How did J.J. Thomson's plum pudding model of the atom differ from Dalton's model?

  • Thomson discovered electrons (which he called 'corpuscles') in 1897, for which he won a Nobel Prize
  • His plum pudding model showed atoms as composed of electrons scattered throughout a spherical cloud of positive charge
  • This model showed that atoms are not indivisible, as Dalton had proposed
• What does the atomic number represent?

  Number of protons in the nucleus
• How does the size of the nucleus compare to the size of the entire atom?

  The nucleus is much smaller than the overall size of the atom
• What is the name of the negatively charged particles that orbit the nucleus of an atom?

  Electrons
• What surrounds the nucleus of an atom?

  Electron shells forming distinct regions
• What are the key differences between the nuclear model and the planetary model of the atom?

  The nuclear model has the positive charge concentrated in the center (the nucleus), while the planetary model has the electrons orbiting around the nucleus like planets around the sun
• Describe the structure of an atom including its charges.

  • Nucleus at the center
  • Contains positive protons
  • Contains neutral neutrons
  • Electron shells surrounding the nucleus
  • Contains negative electrons orbiting