WorksheetsTSNF AP Chemistry
Total questions: 204
Worksheet time: 2hrs 2mins
When an electron is in a higher energy level, it is farther away from the nucleus and has less Coulombic attraction to the nucleus and is therefore easier to remove
True
False
Isotopes of an element have the same number of protons, but different numbers of electrons.
True
False
Cations (+) are smaller than their atoms since you are removing valence electrons that are farther from the nucleus and anions (−) are larger than their atoms since adding extra electrons increases electron-electron repulsions.
True
False
The greater the electronegativity difference between 2 atoms, the more polar the bond becomes.
True
False
% error= (experimental - theoretical)/experimental
True
False
T and V are indirectly related...If you heat a balloon, it will expand.
True
False
One mole of an ideal gas = 22.4 Liters at any temperature or pressure
True
False
Molar Mass = dRT/P
True
False
Real gases behave most like an ideal gas at high temperature and at low pressure. The more polar a gas is and the larger a gas is, the more it will deviate from ideal behavior. Consequently, small, nonpolar gases are the _______ ideal.
Most
Least
(−) ΔH; feels hot; heat is a product; temperature goes up
Exothermic
Endothermic
Breaking bonds is endothermic. Forming bonds is exothermic.
True
False
When calculating ΔH from chemical equations with known enthalpies, if you double reaction coefficients, what happens to the overall ΔH value?
it doubles
it is squared
the sign changes
nothing
When calculating ΔH from chemical equations with known enthalpies, if you reverse the reaction, what happens to the overall ΔH value?
the sign for ΔH changes
it doubles
it is squared
nothing
A single bond is composed of
1 sigma bond
1 pi bond
1 sigma and 1 pi bond
no sigma or pi bonds
A triple bond is composed of
1 sigma bond
1 pi bond
2 pi bonds
1 sigma and 2 pi bonds
Lattice energy is the energy to break an ionic bond in a compound. Lattice energy increases as the ion’s charge increases. Lattice energy decreases as the radii of the ions increase.
True
False
Which is the strongest IMF?
LDF
Dipole dipole
Hydrogen bonding
Ion-dipole
Which would have the strongest IMFs?
CH4
C2H2
C4H8
C8H14
Vapor pressure and volatility decrease as IMF’s increase.
True
False
SiO2 (quartz) and diamonds are ____________________, and they have very high boiling/melting points.
covalent network solids
ionic solids
molecular solids
interstitial alloys
______________ alloys are made when a smaller atom fits into the gaps between larger atoms of a metallic crystal.
Interstitial
Substituitonal
Which is not needed for a reaction to occur?
particles must collide at the correct orientation
particles must collide with a minimum energy
particles must be large enough to break bonds
A first order reaction graph is
ln[A] v time
1/[A] v time
[A] v time
Which of these is false in terms of speeding up reactions?
Adding a catalyst lowers the activation energy
increasing reactant concentration increases collisions
increasing surface area decreases collisions
increasing temperature increases collisions
The taller the “hill” (or activation energy) the slower the reaction.
True
False
The fast step (rate-determining step) will dictate the speed of the reaction, and this step will determine the rate law.
True
False
Catalysts are produced in one step and used up in a later step
True
False
Only (aq), (l), and (g) appear in an equilibrium expression.
True
False
A larger K means there are ______ products at equilibrium
more
less
What happens to K if a reaction is reversed?
1/K
K2
2K
-K
What happens to K is a reaction is doubled?
K2
2K
1/2K
-K
If K<Q, then the reaction shifts to the _________
left
right
If the pressure of a system is increased, which direction will equilibrium shift?
toward the side with less moles of gas
toward the side with more moles of gas
it will not shift
Catalysts and inert gases do not shift an equilibrium.
True
False
What type of alloy is made when the radii of the atoms are similar in size?
interstitial
substitutional
Which atom has the negative dipole in this molecule?
Hydrogen
Fluorine
Neither
In this molecule, Carbon has a formal charge of ____ and Nitrogen has a formal charge of _____.
0, 0
1, 0
0, -1
-1, 0
Combustion reactions produce what two substances?
Water Vapor and Carbon Dioxide
Carbon Dioxide and Oxygen
Oxygen and Water Vapor
As the electronegativity difference between 2 atoms increases, the polarity of the bond ____________________
increases
decreases
What type of bond forms between hydrogen and chlorine?
polar covalent
non-polar covalent
ionic
hydrogen bond
What type of alloy is this?
Interstitial
Substitutional
What is the total # of covalent bonds carbon can form when drawing a Lewis structure?
12
6
4
8
What is the bond angle in BF3?
90
120
109.5
180
What is the bond angle in H2O?
120
90
180
104.5
What is the bond angle in NH3
120
107.3
180
90
What is the hybridization of carbon in CH4?
sp3
sp
sp2
What is the hybridization for carbon in CO2
sp3
sp
sp2
Count the number of sigma and pi bonds in this molecule:
13 sigma, 1 pi
14 sigma, 2 pi
1 sigma, 14 pi
2 sigma, 13 pi
Why are asymmetrical molecules polar?
Their dipoles do not cancel
Their dipoles cancel
What is the hybridization for an oxygen in CO2
sp3
sp
sp2
When a molecular solid melts or boils, which breaks?
Intermolecular forces
Intramolecular bonds
What is the total # of covalent bonds carbon has to make when drawing a Lewis structure?
12
6
4
8
What order is this graph?
Zero
First
Second
Third
What order is this graph?
Zero
First
Second
Third
If you quadruple the concentration and the rate quadruples, what order is this reaction?
zero
first
second
The particles under the purple curve (middle) have an average Kinetic Energy that is proportional to of 500K
True
False
Which step of a reaction mechanism determines the rate?
the slow step
the fast step
the first step
the second step
What order is the half life of Carbon14?
Zero
First
Second
What is the unit for the rate constant (k) for 2nd order reactions?
s-1
M/s
M-1s-1
How does a catalyst speed up a reaction?
Adding more reactant
Providing a pathway that has a lower activation energy
Increasing the activation energy
Increasing binding energy
___________ are produced in one step and used up in a later step and __________________ are present and unchanged in the reactants and the products
intermediates, catalysts
catalysts, intermediates
If a “reaction profile” has a taller ‘hill’ (or activation energy) then the reaction is ____________________?
Faster
Slower
What are the 2 characteristics that an effective collision must have? SELECT TWO
Enough energy to overcome Ea
Molecules in the correct orientations
High enough temperature
Apporpriate intermediates present
What is the rate law for the reaction with this slow elementary step? A + A --> B + B
rate = k[A]2
rate = k[B]2
rate = k[A][B]
rate = k[A]
What is the rate law for the reaction with this slow elementary step? A --> B + C
rate = k[A]2
rate = k[B]2
rate = k[A][B]
rate = k[A]
What is the rate law for the reaction with this slow elementary step? A + 2B --> D + C
rate = k[A]2
rate = k[A][B]2
rate = k[A][B]
rate = k[A]
What is NOT a way to speed up a reaction
Add a catalyst
Decrease the volume
Increase the concentration of reactants
Increase surface area of the solid
Decrease the pressure
Which curve represents the most particles in this Maxwell-Boltzmann curve (# of particles vs. speed)?
Black (peak on the left)
Red (peak in the middle)
Blue (peak on the right)
They all have the same number of particles
Which curve in this Maxwell-Boltzmann distribution represents the highest proportion of particles moving the fastest (# of particles vs. speed)?
Black (peak on the left)
Red (peak in the middle)
Blue (peak on the right)
All particles are moving at the same speed
What order of reaction has a half-life that does not change regardless of the initial concentration?
Zero
First
Second
Third
A system at equilibrium
Must have reactants and products
Must have products only
Must have reactants only
Given the following equilibrium equation,
A (g) + 2B (g) ⇄ AB2 (g) ΔH > 0, which of the following changes will increase the amount of AB2 in the vessel?
Decreasing the temperature
Increasing the concentration of A
Removing a small amount of B
Decreasing the pressure
Given the following equilibrium equation,
A (g) + 2B (g) ⇄ AB2 (g) ΔH < 0, which of the following changes will decrease the amount of AB2 in the vessel?
Increasing the temperature
Increasing the concentration of A
Increasing the pressure
Adding a catalyst
The following system at equilibrium is exothermic. If the temperature is increased...
A (g) + 2B (g) ⇄ AB2 (g)
[A] will increase the most
[B] will increase the most
[AB2] will increase the most
For an exothermic system at equilibrium, if the temperature is increased, the equilibrium will shift towards the...
reactants
products
In a Ksp expression, we always assume that the reactant is made up of
the solid precipitate
the aqueous ions
If Ksp >1, we say the salt is...
soluble
insoluble
If a common ion is present, the solubility of a salt
is increased
is decreased
will remain the same
In an exothermic reaction, the sign of ΔH is ____ and the reaction feels ______
(-), hot
(+), hot
(-), cold
(+), cold
Freezing is an _________________________ process
Endothermic
Exothermic
Vaporizing is an _________________________ process
Endothermic
Exothermic
Breaking bonds is _________________. Forming bonds is ______________________
endothermic, exothermic
exothermic, endothermic
ΔHrxn = ΔH_________________ − ΔH_________________
products, reactants
reactants, products
If a reaction is exothermic, then the bonds formed in the products are ___________________ than the reactant bonds.
stronger/more stable
weaker/less stable
If a reaction is endothermic, then the bonds formed in the products are ___________________ than the reactant bonds.
stronger/more stable
weaker/less stable
According to Hess' Law, if you double the coefficients of a reaction, ΔH will ________________________
Stay the same
Double
Quadruple
Halve
According to Hess' Law, if you reverse a reaction, ΔH will ________________________
Change signs
Double
Be inversed
Halve
_____ Hydrogen-Hydrogen single bond/s are broken and _____ Carbon-Hydrogen single bond/s formed
6; 8
2; 8
2; 10
6; 10
_____ Carbon-Carbon single bond/s are formed
6
2
3
10
Bond enthalpy is the amount of energy is takes to break __________ of a bond.
one mole
one gram
the activation energy
the binding energy
What are the units of ΔHrxn?
kJ
J
kJ/mol
J/mol
Endothermic
absorb energy
release energy
Exothermic
absorb energy
release energy
In the dissolution process, the increase in separation between ions in the solute is
endothermic
exothermic
In a system, the energy lost by the reacting species must be ________________ the energy gained by the surrouding
greater than
less than
equal to
On a potential energy diagram for an endothermic reaction,
the potential energy of the reactants is greater than the potential energy of the products
the potential energy of the reactants is less than the potential energy of the products
the potential energy of the reactants is equal to the potential energy of the products
A temperature is placed in a calorimeter. A solid is dissolved in water in the calorimeter and the temperature of the thermometer increases. The dissolution reaction must be
endothermic
exothermic
Using bond energies to solve for enthalpy,
ΔH = Bond broken - bonds formed
undefined = Bond formed- bonds broken
undefined = products - reactants
undefined = reactants- products
The enthalpy of formation for a lone element is
a number
zero
At equilibrium, rates of the forward and reverse reaction are...
The same
Not the same
A system at equilibrium
Must have reactants and products
Must have products only
Must have reactants only
At equilibrium, concentrations of reactants and products are
equal
constant
At what time does the system first reach equilibrium?
24s
40s
60s
80s
The equilibrium constant expression, Kc, given aA + bB ⇄ cC + dD, is...
Kc = [A]a[B]b[C]c[D]d
Kc = [C]c[D]d[A]a[B]b
Which substance(s) would not be included in a equilibrium constant expression?
NaCl(s)
NaCl(aq)
NaCl(l)
NaCl(g)
If a K value is greater than 1,
more products are present at equilibrium
more reactants are present at equilibrium
If a K value is VERY large,
the reaction has essentially gone to completion
there are more reactants present at equilibrium
If K < Q, the reaction will proceed in the...
reverse direction to reach equilibrium
forward direction to reach equilibrium
When a reaction at equilibrium is reversed,
the K value's sign is flipped
the K value is divided by 2
the K value is inverted
To calculate the K of an overall reaction from individual reaction K values, the individual K values are
added
subtracted
multiplied
divided
When the coefficient of a reaction is multiplied by a factor x,
the K value is multipled by x
the K value is divided by x
the K value is raised to the power x
Given the following equilibrium equation,
A (g) + 2B (g) ⇄ AB2 (g) ΔH > 0, which of the following changes will increase the amount of AB2 in the vessel?
Decreasing the temperature
Increasing the concentration of A
Removing a small amount of B
Decreasing the pressure
Given the following equilibrium equation,
A (g) + 2B (g) ⇄ AB2 (g) ΔH < 0, which of the following changes will decrease the amount of AB2 in the vessel?
Increasing the temperature
Increasing the concentration of A
Increasing the pressure
Adding a catalyst
The following system at equilibrium is exothermic. If the temperature is increased...
A (g) + 2B (g) ⇄ AB2 (g)
[A] will increase the most
[B] will increase the most
[AB2] will increase the most
For an endothermic system at equilibrium, if the temperature is decreased, the equilibrium will shift towards the...
reactants
products
In a Ksp expression, we always assume that the reactant is made up of
the solid precipitate
the aqueous ions
Why are all gas mixtures considered to be homogenous?
The gas particles mix uniformly without distinct areas of concentration
The gas particles mix in distinct areas of concentration
The gas particles cannot be separated from each other
The gas particles are in constant random motion
Why are gases compressible?
Gas particles are very small but take up large volumes of space
Gas particles are very small and take up small volumes of space
Gas particles are strong attracted to one another.
How are P and V related?
When Pressure increases Volume increases
When Pressure increases Volume decreases
When Pressure decreases Volume decreases
What causes gas pressure?
The constant collisions of gas particle on the walls of a container
The decrease in temperature when gas particles move slower
The collision of gas particles with each other
How are T and V related?
When Temperature increases Volume increases
When Temperature increases Volume decreases
When Temperature decreases Volume increases
How are T and P related?
When Temperature decreases Pressure increases
When Temperature increases Pressure decreases
When Temperature increases Pressure increases
In the equation PV = nRT what are the units for T, V and P?
Celcius, L, atm
Kelvin, ml, torr
Kelvin, L atm
At STP what is the volume of one mole of an ideal gas?
14.4 L
22.4 L
11.2 L
How are gas pressure and number of moles related?
When # moles decreases P increases
When # moles decreases P decreases
When # moles increases P increases
When # of moles increases P decreases
Which of the following gases will move the fastest if they are at the same temperature?
He Ar
He will move slower because it is smaller than Ar
He will move faster because it is smaller than Ar
He will move faster because it is larger than Ar
When carbon dioxide gas is collected over water, what accounts for the total pressure in the container?
carbon dioxide gas only
water vapor only
carbon dioxide gas and water vapor
In what conditions do real gases behave most like ideal gases?
low T and high P
low P and high T
high T and high P
What gases deviate the most form ideal gas behavior?
polar and large gas particles
nonpolar and large gas particles
polar and small gas particles
When a molecular solid melts or boils, which bonds break?
Intermolecular
Intramolecular
Name a property that increases as Intermolecular Forces increase.
Vapor pressure
Conductivity
Melting point
Solubility
What compound could this be?
CO2
NH3
H2S
CH4
Draw the Lewis Dot structure for PCl5 and determine the predicted molecular geometry
octahedral
trigonal pyramidal
seesaw
trigonal bipyramidal
Filtering separates mixtures based on differences in what property?
Chemical
Solubility
Particle size
Density
What is the equation for calculating the density of a substance?
D=m/v
m=D/v
D=v*m
D=v/m
When an electron is in a lower energy level, it is ________________ away from the nucleus
Closer
Farther
When reading a PES (Photoelectric Spectroscopy) graph, what does the height of a peak represent?
The number of electrons
The number of protons
The mass or the isotope
The amount of energy the electron has
Isotopes of an element have the same number of __________, but different number of __________.
protons, neutrons
neutrons, protons
protons, electrons
electrons, protons
When reading a PES (Photoelectron Spectroscopy) graph, a larger binding energy means that the electrons are _________________ the nucleus?
Closer to
Farther from
Distillation separates mixtures based on differences in what property?
Solubility
Boiling Point
Particle Size
State of Matter
What type of change conserves mass?
none
chemical
physical
chemical and physical
When an electron is in a higher energy level, it has ___________ Coulombic attraction to the nucleus
More
Less
What is the measurement of the burette? (in mL)
6.6mL
6.64mL
7.36mL
7.3mL
Which orbital comes after 4s?
3d
5s
4p
4d
Are cations larger or smaller than their neutral atoms?
Larger
Smaller
Same size
Which piece of glassware is the most precise
beaker
graduated cylinder
burette
test tube
Moving across a row (L to R) on the periodic table, Zeff _________________
Increases
Decreases
Stays the same
What type of change separates a compound into elements?
physical
chemical
chemical and physical
Why do atoms get smaller moving across a period (L to R) on the periodic table?
More protons (q) to attract the electrons
Fewer protons (q) to attract the electrons
More energy shells (r) so it can't attract the electrons
Fewer energy shells (r) so it attracts the electrons closer
Why are anions larger than their neutral atoms?
More shielding that repels the other electrons
Fewer protons to attract electrons
More electrons to attract protons
More Zeff to attract electrons
Which piece of glassware is the least precise?
graduated cylinder
beaker
burette
When an electron is in a lower energy level, it has a ________________ 1st ionization energy
Higher
Lower
Same
Which electrons are removed first when making a cation?
s
p
d
f
What do mass spectroscopy graphs measure?
Mass of isotopes
Mass of protons
Energy of electrons
Number of electrons
What is the bond angle in BF3?
90
120
109.5
180
When reading a PES graph, a larger binding energy means that the electrons are ____________ from the nucleus?
closer
farther
the same distance
Which orbital comes after 4p?
5s
4s
3d
4p
Fill in the blanks germanium is a ________________, hydrogen is a _________________ and uranium is a ________________
metal, non-metal, metalloid
metalloid, non-metal, metal
non-metal, metal, metalloid
Are asymmetrical molecules polar or nonpolar?
Polar
non-polar
neither
List the 3 Intermolecular forces from weakest to strongest
hydrogen bonding, london dispersion, dipole dipole
london dispersion, hydrogen bonding, dipole dipole
london dispersion, dipole dipole, hydrogen bonding
dipole dipole, hydrogen bonding, london dispersion
List ALL the Intermolecular forces that exist in PCl3
hydrogen bonding, london dispersion
london dispersion, hydrogen bonding, dipole dipole
london dispersion, dipole dipole
london dispersion
Are anions larger or smaller than their neutral atoms?
Larger
Smaller
Same size
“More polarizable” refers to which Intermolecular Force?
hydrogen bonding
london dispersion
dipole dipole
What is an example of a covalent network solid?
Salt
Diamond
Sugar
Water
Name a property that decreases as Intermolecular Forces increase.
Vapor pressure
Conductivity
Melting point
Solubility
P and V are ___________________ related?
inversely
directly
The more molar mass a gas has, the_________________ it moves
faster
slower
Average Kinetic Energy is another term for _____________.
Heat
Temperature
Pressure
Activation energy
Real gases behave most like an ideal gas at what conditions of temperature and pressure?
High T, Low P
High P, Low T
High V, Low T
When an electron is in a lower energy level, it has a ___________ 1st ionization energy
Higher
Lower
What is the hybrid orbital used in CH4?
sp3
sp
sp2
What is the hybrid orbital used in CO2
sp3
sp
sp2
What is the bond angle in SO2
120
90
180
109.5
Reactions with what sign for ΔH and ΔS are ALWAYS thermodynamically favorable?
+, +
-,-
-, +
+, -
Thermodynamically favorable reactions have what sign for ΔG ?
negative
positive
If the entropy term is unfavorable and the enthalpy term is favorable, at what temperatures will ΔG be negative?
low
high
all
none
At equilibrium, what is the value of ΔG ?
zero
one
need more information
If a reaction increases the number of moles of gas, then the sign for entropy is what?
positive
negative
If ΔG is negative, the Keq is greater than or less than 1?
greater
less
When ΔG=0, K = 1 .
true
false
Given their standard reduction potentials, which of the species is going to be oxidized?
Cu2+(aq)+2e− → Cu(s) Eo=0.34 V
Zn2+(aq)+2e− → Zn(s) Eo=−0.76 V
Cu
Zn
CuSO4
ZnSO4
What does the magnitude of Ksp tell us about a salt?
How much it can dissociate
The pH at equilibirium
How much solid is present
The molar mass of the ions
On a PES graph, what quantity is proportional to peak height?
The number of protons
The molar mass of the isotope
The number of electrons
The binding energy of the electrons
What two characteristics must an effective collision have?
Sufficient kinetic energy
High enough pressure
Correct orientation
Sufficient potential energy
Which of these is NOT a strong acid?
HF
HCl
HBr
HI
How will the percent ionization of a weak acid change if water is added to it?
It will increase
It will decrease
It will stay the same
Not enough information
According to Coulomb's Law, which TWO properties of an electron determine the strength of attraction to the nucleus?
Distance between e- and nucleus
Effective nuclear charge
Number of neutrons
Atomic mass
If Q increases, the voltage (Ecell) of the battery (a) relative to E°.
Elements in the same (a) on the periodic table usually have similar chemical and physical properties.
Temperature is the _________________ of particles.
total heat energy
maximum kinetic energy
average kinetic energy
average mass energy
Adding conjugate base to a weak acid solution (a) the percent ionization of the acid.
Electrons flow from the (a) to the (b) .
If [A] vs time is linear, the reactions is -
zero order
first order
second order
third order
If 1/[A] vs time is linear, the reactions is -
zero order
first order
second order
third order
On average, particles of a has with a high mass will move (a) than a gar with a low mass at the same temperature.
If a 100 g sample of a radioactive isotope has a half-life of 2 days, how many days will it take to reach a mass of 25 g?
2 days
4 days
12.5 days
6 days
At constant volume, decreasing the temperature of a has will cause the pressure to -
increase
decrease
stay the same
depends on the gas
