SCH4U : ATOMIC THEORY FINAL TEST 2026
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◍ Beta particle.
Answer: Consists of a stream of high speed electrons; Symbol is 0/-1e; This
type of radiation is 100x more penetrating than α-particles. It can pass 1-2
mm through solid material, including clothing and skin.
◍ Frequency.
Answer: The number of waves that pass a given point per second.
◍ Octet Rule.
Answer: States that atoms will gain, lose, or share electrons in order to
obtain 8 electrons in its valence shell
◍ Nuclear chain reaction.
Answer: A continuous series of fission reactions that produce a tremendous
amount of energy
◍ Sublevels.
Answer: Refers to electron orbitals designated s, p, d or f. These have
characteristic shapes which can be used to explain and predict the chemical
bonds that atoms can form.
◍ JJ Thomson.
Answer: Scientist who discovered electrons.
◍ Alpha decay.
Answer: The emission of alpha particles. Each lost particle results in the
creation of an isotope that has a mass number that is 4 less than the parent
atom and an atomic number that is 2 less
, ◍ Gold Foil Experiment.
Answer: Rutherford did this experiment using alpha particles. Deflected
alpha particles proved there was a small dense positively charged nucleus.
◍ Dalton's Atomic Theory.
Answer: Stated that 1) each element is made of extremely small particles
called atoms that are indivisible; 2) All atoms of a given element are
identical, but they differ from those of any other element; 3) Atoms are
neither created or destroyed in any chemical rxn; and 4) a given compound
always has the same relative #s and kinds of atoms. Proven over time to not
be entirely accurate, but it was close!
◍ Cation.
Answer: An atom that lost electrons and therefore has a positive charge.
◍ Average atomic mass.
Answer: The mass of a single atom; Listed on the periodic table as a decimal
# that is the weighted average mass of all known isotopes of an element
◍ Atomic number.
Answer: The number of protons in an atom's nucleus; the element's
"address" on the periodic table
◍ Quantum Mechanical Model.
Answer: The current model of the atom in which electrons move like waves,
exist in discrete energy levels and sublevels in a cloud-like formation
outside the nucleus, and have their location described in terms of the
mathematical probability of being found in a certain region of space called
orbitals.
◍ John Dalton.
Answer: Proposed the 4pt atomic theory
◍ Electromagnetic repulsion.
Answer: Refers to the fact that similarly charged particles repel each other
◍ Eugene Goldstein.
QUESTIONS WITH CORRECT ANSWERS
GRADED A+
◍ Beta particle.
Answer: Consists of a stream of high speed electrons; Symbol is 0/-1e; This
type of radiation is 100x more penetrating than α-particles. It can pass 1-2
mm through solid material, including clothing and skin.
◍ Frequency.
Answer: The number of waves that pass a given point per second.
◍ Octet Rule.
Answer: States that atoms will gain, lose, or share electrons in order to
obtain 8 electrons in its valence shell
◍ Nuclear chain reaction.
Answer: A continuous series of fission reactions that produce a tremendous
amount of energy
◍ Sublevels.
Answer: Refers to electron orbitals designated s, p, d or f. These have
characteristic shapes which can be used to explain and predict the chemical
bonds that atoms can form.
◍ JJ Thomson.
Answer: Scientist who discovered electrons.
◍ Alpha decay.
Answer: The emission of alpha particles. Each lost particle results in the
creation of an isotope that has a mass number that is 4 less than the parent
atom and an atomic number that is 2 less
, ◍ Gold Foil Experiment.
Answer: Rutherford did this experiment using alpha particles. Deflected
alpha particles proved there was a small dense positively charged nucleus.
◍ Dalton's Atomic Theory.
Answer: Stated that 1) each element is made of extremely small particles
called atoms that are indivisible; 2) All atoms of a given element are
identical, but they differ from those of any other element; 3) Atoms are
neither created or destroyed in any chemical rxn; and 4) a given compound
always has the same relative #s and kinds of atoms. Proven over time to not
be entirely accurate, but it was close!
◍ Cation.
Answer: An atom that lost electrons and therefore has a positive charge.
◍ Average atomic mass.
Answer: The mass of a single atom; Listed on the periodic table as a decimal
# that is the weighted average mass of all known isotopes of an element
◍ Atomic number.
Answer: The number of protons in an atom's nucleus; the element's
"address" on the periodic table
◍ Quantum Mechanical Model.
Answer: The current model of the atom in which electrons move like waves,
exist in discrete energy levels and sublevels in a cloud-like formation
outside the nucleus, and have their location described in terms of the
mathematical probability of being found in a certain region of space called
orbitals.
◍ John Dalton.
Answer: Proposed the 4pt atomic theory
◍ Electromagnetic repulsion.
Answer: Refers to the fact that similarly charged particles repel each other
◍ Eugene Goldstein.
