CHEM 134 FINAL EXAM QUESTIONS WITH
CORRECT DETAILED ANSWERS ||
ALREADY GRADED A+ <RECENT
VERSION>
Reactions occur only in what SI unit? - ANSWER moles
What is an endothermic process? - ANSWER Heat is transferred from the
surroundings to the system.
What happens to heat in an endothermic reaction? - ANSWER Heat is
absorbed.
How does an endothermic reaction feel to the touch? - ANSWER It feels cool
or cold to the touch. Temperature decreases
, What is an exothermic reaction? - ANSWER A reaction where heat is
transferred from the system to the surroundings.
What happens to heat in an exothermic reaction? - ANSWER Heat is released
or evolved.
How does an exothermic reaction feel to the touch? - ANSWER It feels warm
or hot to the touch.
What happens to the temperature during an exothermic reaction? -
ANSWER The temperature increases.
What does Dalton's Atomic Theory state about elements? - ANSWER Elements
are composed of atoms.
According to Dalton's Atomic Theory, how do atoms of the same element compare
to atoms of different elements? - ANSWER Atoms of the same element are
identical, but differ from other elements.
What does Dalton's Atomic Theory say about the mixing of elements? -
ANSWER Elements can mix together.
When do atoms change according to Dalton's Atomic Theory? -
ANSWER Atoms only change when mixed with other elements.
What are cathode rays composed of? - ANSWER Electrons
,In what direction do cathode rays travel? - ANSWER In a straight line
What happens to cathode rays when external electric and magnetic fields are
applied? - ANSWER They are bent
Who discovered cathode rays? - ANSWER J.J. Thomson
Where do cathode rays travel from and to? - ANSWER From the negatively
charged cathode to the positively charged anode
Rutherford experiment - ANSWER gold foil experiment with alpha particles
Most of the volume of atoms is empty space
The nucleus must be positively charged to deflect an alpha particle
What is a mole (mol)? - ANSWER A unit of amount of material containing an
Avogadro number of particles.
How is one mole defined? - ANSWER As the number of carbon-12 atoms in 12
grams of carbon-12.
What are alpha particles? - ANSWER Alpha particles are the densest type of
radiation.
, What are gamma particles? - ANSWER Gamma particles have no mass and are
a form of high-energy radiation.
What are beta particles? - ANSWER Beta particles are electrons.
allotropes of carbon - ANSWER diamond and graphite
Accuracy vs. Precision - ANSWER accuracy: how close the experimental value
is to the accepted value; precision: how closely measured values agree with each
other
allotropes of oxygen - ANSWER dioxygen and ozone
incomplete combo - ANSWER insufficient oxygen, fuel only partially oxidized.
systematic error - ANSWER Error that shifts all measurements in a
standardized way. Decreases accuracy. Can result in bias
central tendency - ANSWER mean, median, mode
accuracy evaluation - ANSWER absolute error (E=observed-accepted)
relative error (RE%= obs-acc/acc x100)
dimensional analysis - ANSWER desired unit = given unit x (desired/given
unit)
CORRECT DETAILED ANSWERS ||
ALREADY GRADED A+ <RECENT
VERSION>
Reactions occur only in what SI unit? - ANSWER moles
What is an endothermic process? - ANSWER Heat is transferred from the
surroundings to the system.
What happens to heat in an endothermic reaction? - ANSWER Heat is
absorbed.
How does an endothermic reaction feel to the touch? - ANSWER It feels cool
or cold to the touch. Temperature decreases
, What is an exothermic reaction? - ANSWER A reaction where heat is
transferred from the system to the surroundings.
What happens to heat in an exothermic reaction? - ANSWER Heat is released
or evolved.
How does an exothermic reaction feel to the touch? - ANSWER It feels warm
or hot to the touch.
What happens to the temperature during an exothermic reaction? -
ANSWER The temperature increases.
What does Dalton's Atomic Theory state about elements? - ANSWER Elements
are composed of atoms.
According to Dalton's Atomic Theory, how do atoms of the same element compare
to atoms of different elements? - ANSWER Atoms of the same element are
identical, but differ from other elements.
What does Dalton's Atomic Theory say about the mixing of elements? -
ANSWER Elements can mix together.
When do atoms change according to Dalton's Atomic Theory? -
ANSWER Atoms only change when mixed with other elements.
What are cathode rays composed of? - ANSWER Electrons
,In what direction do cathode rays travel? - ANSWER In a straight line
What happens to cathode rays when external electric and magnetic fields are
applied? - ANSWER They are bent
Who discovered cathode rays? - ANSWER J.J. Thomson
Where do cathode rays travel from and to? - ANSWER From the negatively
charged cathode to the positively charged anode
Rutherford experiment - ANSWER gold foil experiment with alpha particles
Most of the volume of atoms is empty space
The nucleus must be positively charged to deflect an alpha particle
What is a mole (mol)? - ANSWER A unit of amount of material containing an
Avogadro number of particles.
How is one mole defined? - ANSWER As the number of carbon-12 atoms in 12
grams of carbon-12.
What are alpha particles? - ANSWER Alpha particles are the densest type of
radiation.
, What are gamma particles? - ANSWER Gamma particles have no mass and are
a form of high-energy radiation.
What are beta particles? - ANSWER Beta particles are electrons.
allotropes of carbon - ANSWER diamond and graphite
Accuracy vs. Precision - ANSWER accuracy: how close the experimental value
is to the accepted value; precision: how closely measured values agree with each
other
allotropes of oxygen - ANSWER dioxygen and ozone
incomplete combo - ANSWER insufficient oxygen, fuel only partially oxidized.
systematic error - ANSWER Error that shifts all measurements in a
standardized way. Decreases accuracy. Can result in bias
central tendency - ANSWER mean, median, mode
accuracy evaluation - ANSWER absolute error (E=observed-accepted)
relative error (RE%= obs-acc/acc x100)
dimensional analysis - ANSWER desired unit = given unit x (desired/given
unit)
