1.1.2 Subatomic Particles: Protons, Neutrons, and Electrons

• What are subatomic particles in an atom?

  Tiny bits inside an atom
• Protons have a positive charge and are located in the nucleus.


  True
• What are the fundamental particles shown in the image?

  • Gluon
  • Quark
  • Antiquark
  • Electron
  • Positron
  • J/ψ meson
• What is the charge of a neutron?

  Neutral (0)
• What is the name of the force carrier particle shown in the image?

  Photon
• What is the relationship between quarks and hadrons like protons and neutrons?

  Quarks are the fundamental constituents that make up hadrons like protons and neutrons
• How does the mass radius of a proton compare to the size of an electron?

  • The mass radius of a proton is much smaller than the size of an electron.
  • The proton has a mass radius while the electron is depicted as a point-like particle.
• How do the parts of an atom interact with each other?

  • Protons and electrons attract each other due to opposite charges
  • Neutrons have no charge and do not directly interact with protons or electrons
  • The nucleus (protons and neutrons) is held together by the strong nuclear force
• Neutrons help stabilize the nucleus by spacing out positively charged protons.

  True
• What type of particle is represented by the blue spheres in the image?

  Electron
• What is the charge of a proton?

  Positive
• Electrons have a significant mass comparable to protons.

  False
• What is the charge of an electron?

  Negative
• What is the mass of a neutron?

  1 amu
• Match the subatomic particle with its charge:

  Proton ↔️ Positive (+)

  Neutron ↔️ Neutral (0)

  Electron ↔️ Negative (-)
• Why is the mass of an electron considered negligible?

  Compared to protons and neutrons
• Electrons are located in the nucleus of an atom.

  False
• What is the relationship between quarks and gluons?

  • Gluons are the force carriers that bind quarks together to form hadrons like protons and neutrons.
  • Quarks interact with each other through the exchange of gluons.
• How does the J/ψ meson differ from the other fundamental particles shown in the image?

  The J/ψ meson is a bound state of a quark-antiquark pair, unlike the other point-like fundamental particles
• How does the Bohr model differ from the modern quantum mechanical model of the atom?

  • Bohr model has discrete electron orbits, quantum model has electron probability clouds
  • Bohr model explains atomic spectra, quantum model provides a more complete description of atomic structure and behavior
  • Bohr model is a simplified classical model, quantum model is based on quantum mechanics
• Why is understanding subatomic particles important?

  Explains element behavior
• What are the three main parts of an atom?

  • Proton
  • Electron
  • Neutron
• What is the role of the J/ψ meson in this diagram?

  • The J/ψ meson is a bound state of a charm quark and a charm antiquark.
  • It serves as an example of a hadron composed of a quark-antiquark pair.
• What type of particle is represented by the orange spheres in the image?

  Neutron
• What is the formula to calculate the radius of the nth Bohr orbit?

  $r_n =$$\frac{n^2 h^2}{4\pi^2 m_e e^2}$

  where:

  • $r_n$ is the radius of the nth orbit
  • $n$ is the principal quantum number
  • $h$ is Planck's constant
  • $m_e$ is the mass of an electron
  • $e$ is the charge of an electron
• Where are protons located?

  nucleus
• What is the name of the central part of an atom?

  Nucleus
• Where are the protons and neutrons located in an atom?

  The protons and neutrons are located in the nucleus of the atom.
• What are the key components of the Bohr atomic model?

  • Nucleus with protons and neutrons
  • Electrons orbiting the nucleus in discrete energy levels
  • Electrons can only occupy certain allowed energy levels
  • Electrons can jump between energy levels by absorbing or emitting photons
• What is the purpose of the electrons in an atom?

  Electrons provide the negative electrical charge to balance the positive charge of the protons
• What is the name of the atomic model shown in the image?

  Bohr atomic model
• What is the mass of a proton in atomic mass units (amu)?

  1
• How does the number of protons, neutrons, and electrons determine the identity and properties of an atom?

  The number of protons determines the element, the number of neutrons determines the isotope, and the number of electrons determines the charge and chemical reactivity
• Where are protons located within an atom?

  Nucleus
• What is the charge of a neutron?

  0
• How does the Bohr model explain the stability of atoms?

  • Electrons occupy specific energy levels around the nucleus
  • Electrons cannot exist between energy levels
  • This prevents the electrons from radiating energy and collapsing into the nucleus
• If an atom has 3 protons and 4 neutrons, how many electrons would it have to be electrically neutral?

  3 electrons
• Electrons orbit the nucleus in specific paths called shells.


  True
• What type of particle is represented by the green spheres in the image?

  Proton
• What is the charge of an electron?

  -1