CEM 141 EXAM 3 2026 FINAL PAPER
COMPLETE QUESTIONS AND ANSWERS FULL
SOLUTION
◉ Blackbody radiation (Quantum theory of energy observations).
Answer: This is what we observe when we see things glowing. A
solid object emits visible light when it is heated above 800k. As temp
increases, a heated metal rod will glow first red, then orange, etc.
and finally white-hot (Have to observe certain amount of energy to
see a specific change in color)
Any object (including atoms) can emit or absorb onlycertain
quantities of energy
◉ Photoelectric effect (Quantum theory of energy observations).
Answer: This is when light is shined on metal, the light has to be a
certain wavelength. This is because the metal cannot "store" energy
to emit a photoelectron so the light has to be high enough in
frequency to emit a photoelectron
Presence of a threshold frequency, not intensity. Below a certain
frequency, no electrons are ejected no matter the intensity.
◉ Atomic line spectra (Quantum theory of energy observations).
,Answer: These are specific absorption patterns for each atom. The
ground and excited state for each element is different and as a result,
produces different colors. As more electrons are added, it becomes
more difficult to know what colors are emitted. (it shows the colors
(the wavelengths) of the light that allows electrons in that element
to jump from one energy state to another)
◉ What energy level is the ground state.
Answer: lowest energy level
◉ e=mc^2.
Answer: matter and energy are alternate forms of the same entity
◉ Electrons as a wave and particle.
Answer: All matter exhibits properties of waves and particles but
typically only talk abt matter as a particle (matter such as a baseball
does have a very small wavelength -> so small taht cant see).
Electrons have wave-like motion and therefore have only certain
allowable frequencies and energies. Since elecrtons are so small,
their wavelength is more noticable
◉ De Broglie Wavelength.
Answer: what the wavelength is of an object
, ◉ Heisenburg's uncertainty principle.
Answer: Cant know position and momentum of a moving particle at
the same time -> More we know about the speed, less we know
about the position
◉ Wave functions.
Answer: The matter-wave of the electron occupies the space near
the nuclues and is continuous influenced by it (need to describe
where electrons might be)
◉ Schrodinger wave equation.
Answer: Allows us to solve for the energy states associated with a
particular atomic orbital. Solutions to the wave equation are called
wave functions (𝜓).
◉ Quantum numbers.
Answer: where electrons is mostly located and its characteristics.
The more quantum numbers we can define, the more specific we are
about where the electron may be. No two electrons in the same atom
can ahve the same 4 quantum numbers
◉ Principle quantum number (n).
Answer: Indicate the relative size of the orbital and its relative
distance from the nucleus. It describes the energy level, the lower
COMPLETE QUESTIONS AND ANSWERS FULL
SOLUTION
◉ Blackbody radiation (Quantum theory of energy observations).
Answer: This is what we observe when we see things glowing. A
solid object emits visible light when it is heated above 800k. As temp
increases, a heated metal rod will glow first red, then orange, etc.
and finally white-hot (Have to observe certain amount of energy to
see a specific change in color)
Any object (including atoms) can emit or absorb onlycertain
quantities of energy
◉ Photoelectric effect (Quantum theory of energy observations).
Answer: This is when light is shined on metal, the light has to be a
certain wavelength. This is because the metal cannot "store" energy
to emit a photoelectron so the light has to be high enough in
frequency to emit a photoelectron
Presence of a threshold frequency, not intensity. Below a certain
frequency, no electrons are ejected no matter the intensity.
◉ Atomic line spectra (Quantum theory of energy observations).
,Answer: These are specific absorption patterns for each atom. The
ground and excited state for each element is different and as a result,
produces different colors. As more electrons are added, it becomes
more difficult to know what colors are emitted. (it shows the colors
(the wavelengths) of the light that allows electrons in that element
to jump from one energy state to another)
◉ What energy level is the ground state.
Answer: lowest energy level
◉ e=mc^2.
Answer: matter and energy are alternate forms of the same entity
◉ Electrons as a wave and particle.
Answer: All matter exhibits properties of waves and particles but
typically only talk abt matter as a particle (matter such as a baseball
does have a very small wavelength -> so small taht cant see).
Electrons have wave-like motion and therefore have only certain
allowable frequencies and energies. Since elecrtons are so small,
their wavelength is more noticable
◉ De Broglie Wavelength.
Answer: what the wavelength is of an object
, ◉ Heisenburg's uncertainty principle.
Answer: Cant know position and momentum of a moving particle at
the same time -> More we know about the speed, less we know
about the position
◉ Wave functions.
Answer: The matter-wave of the electron occupies the space near
the nuclues and is continuous influenced by it (need to describe
where electrons might be)
◉ Schrodinger wave equation.
Answer: Allows us to solve for the energy states associated with a
particular atomic orbital. Solutions to the wave equation are called
wave functions (𝜓).
◉ Quantum numbers.
Answer: where electrons is mostly located and its characteristics.
The more quantum numbers we can define, the more specific we are
about where the electron may be. No two electrons in the same atom
can ahve the same 4 quantum numbers
◉ Principle quantum number (n).
Answer: Indicate the relative size of the orbital and its relative
distance from the nucleus. It describes the energy level, the lower
