MSU CEM 141 FINAL EXAM
UPDATED PRACTICE EXAM WITH
COMPREHENSIVE QUESTIONS AND
DETAILED, INSTRUCTOR-ALIGNED
EXPLANATIONS
scientific question - Answer-can be answered by doing experiments,
making observation, taking measurements, etc. in a replicable way
Lights acts as what? - Answer-Particle and wave.
scientific model - Answer-drawing, graph, diagram, equation. represent
many chemical entities.
Wavelength - Answer-The distance (m) of waves from peak to peak.
Short: x-ray (red), long: infrared (blue)
Short - higher energy
Long - lower energy
scientific theory - Answer-A well tested concept that explains a wide range
of observations (explains why). changes with time. Explains the underlying
cause of a range of phenomena
,Frequency (V) - Answer-The number of wavefronts per second. Highest:
x-ray
scientific law - Answer-A theory that has been tested by and is consistent
with generations of data. a rule that describes a pattern in nature (explains
what)
Velocity of Light - Answer-C = 3.00 X 10^8
= wavelength X frequency
scientific explanation - Answer-claim, evidence, reasoning
Amplitude - Answer-The intensity, height of peaks of waves. Highest: blue
light
size of an atom - Answer-0.1 x 10^-9m
Energy of Wave (J) - Answer-Increases as frequency increases and as
wavelength decreases. Highest: x-ray
Greek philosophers atomic theory - Answer--first atomic theory
-elements: earth, fire, water, air
-constantly in motion
-made of mostly empty space
Range of Wavelengths - Answer-10^-16 - 10^8 = 24. Only a third are
visible
Black Body Radiation - Answer-When a mass is heated it emits a type of
EM radiation, at very high temps the mass becomes "white hot" because all
wavelengths of visible light become equally intense
molecular structure of a substance determines ___ - Answer-the
observable properties
atom - Answer-smallest distinguishable part of an element
, Photoelectric Effect - Answer-Metals emit electrons when electromagnetic
radiation shines on the surface, light is transfers energy to the electrons at
the metal's surface where it's transformed into KE that gives the electrons
enough energy to leave the atom
Depends on frequency not intensity
how many atoms are naturally occurring? - Answer-91 naturally occurring
elements
How many electrons are emitted if the light is below it's threshold frequency
no matter the intensity? - Answer-None.
Dalton's atomic theory (1800s) - Answer--elements composed of small,
indivisible, indestructible, particles (atoms)
-all atoms of each element are identical (mass/properties)
-no subatomic particles
-compounds are formed by combos of atoms from 2+ elements
-chemical reactions occur from rearrangement of atoms
What increases the number of electrons to be emitted by the photoelectric
effect? - Answer-Intensity.
JJ Thomson - Answer--first person to provide evidence of electron
-cathode ray tube
-plum pudding model
-particles carried electric charge
A particle that transfers light energy with a definable energy, emits one
electron
energy of = h (6.626 x 10^-34 J) - Answer-Photon.
cathode ray tube - Answer--JJ Thomson
-electron particles were emitted from cathodes
-particles carried electric charge
-ray was independent of the element it came from
-particles identical regardless of cathode
-proved all atoms contained electrons
UPDATED PRACTICE EXAM WITH
COMPREHENSIVE QUESTIONS AND
DETAILED, INSTRUCTOR-ALIGNED
EXPLANATIONS
scientific question - Answer-can be answered by doing experiments,
making observation, taking measurements, etc. in a replicable way
Lights acts as what? - Answer-Particle and wave.
scientific model - Answer-drawing, graph, diagram, equation. represent
many chemical entities.
Wavelength - Answer-The distance (m) of waves from peak to peak.
Short: x-ray (red), long: infrared (blue)
Short - higher energy
Long - lower energy
scientific theory - Answer-A well tested concept that explains a wide range
of observations (explains why). changes with time. Explains the underlying
cause of a range of phenomena
,Frequency (V) - Answer-The number of wavefronts per second. Highest:
x-ray
scientific law - Answer-A theory that has been tested by and is consistent
with generations of data. a rule that describes a pattern in nature (explains
what)
Velocity of Light - Answer-C = 3.00 X 10^8
= wavelength X frequency
scientific explanation - Answer-claim, evidence, reasoning
Amplitude - Answer-The intensity, height of peaks of waves. Highest: blue
light
size of an atom - Answer-0.1 x 10^-9m
Energy of Wave (J) - Answer-Increases as frequency increases and as
wavelength decreases. Highest: x-ray
Greek philosophers atomic theory - Answer--first atomic theory
-elements: earth, fire, water, air
-constantly in motion
-made of mostly empty space
Range of Wavelengths - Answer-10^-16 - 10^8 = 24. Only a third are
visible
Black Body Radiation - Answer-When a mass is heated it emits a type of
EM radiation, at very high temps the mass becomes "white hot" because all
wavelengths of visible light become equally intense
molecular structure of a substance determines ___ - Answer-the
observable properties
atom - Answer-smallest distinguishable part of an element
, Photoelectric Effect - Answer-Metals emit electrons when electromagnetic
radiation shines on the surface, light is transfers energy to the electrons at
the metal's surface where it's transformed into KE that gives the electrons
enough energy to leave the atom
Depends on frequency not intensity
how many atoms are naturally occurring? - Answer-91 naturally occurring
elements
How many electrons are emitted if the light is below it's threshold frequency
no matter the intensity? - Answer-None.
Dalton's atomic theory (1800s) - Answer--elements composed of small,
indivisible, indestructible, particles (atoms)
-all atoms of each element are identical (mass/properties)
-no subatomic particles
-compounds are formed by combos of atoms from 2+ elements
-chemical reactions occur from rearrangement of atoms
What increases the number of electrons to be emitted by the photoelectric
effect? - Answer-Intensity.
JJ Thomson - Answer--first person to provide evidence of electron
-cathode ray tube
-plum pudding model
-particles carried electric charge
A particle that transfers light energy with a definable energy, emits one
electron
energy of = h (6.626 x 10^-34 J) - Answer-Photon.
cathode ray tube - Answer--JJ Thomson
-electron particles were emitted from cathodes
-particles carried electric charge
-ray was independent of the element it came from
-particles identical regardless of cathode
-proved all atoms contained electrons
