chemistry final exam
which of the following is an exothermic reaction
C3H8 + 5O2 -------> 3CO2 4H2O; delta H= -2220 kJ
2C6H6 + 15O2 -----> 12CO2 + 6H2O; how many liters would 6 moles of CO2 occupy at STP
134
how many liters of hydrogen react with 2 moles of nitrogen at STP in the following reaction: N2+3H2 ------> 2NH3
134L
what is the percentage composition of Al in the compound Al2(SO4)3
15.8%
in the equation, 2KCl + 3O2 ------> 2KClO3, what mass of potassium chlorate is formed when 10.0 g of potassium chloride react with excess oxygen
16.4 g
a breathing mixture used by deep-sea divers contains helium, oxygen, and carbon dioxide. what is the partial pressure of O2 if the total pressure is 101.4 kPa, and P(He)= 82.5 kPa and P(CO2)= .4 kPa
18.5 kPa
the specific heat of silver is .24 J/gC. how much heat must be added to a silver block of mass 86 g to raise its temperature by 9.0 degrees celsius
190 J
an air-filled balloon has a volume of 225 L at .94 atm and 25C. soon after, the pressure changes to .99 atm and the temperature changes to 0C. what is the new volume of the balloon
195.72 atm
2P + 3Br2 ------> 2PBr3; what is the molar ratio of phosphorous to phosphorous tribromide
1:1
in the balanced equation: 2H2 + O2 ----> 2H2O
2 moles of hydrogen react with 1 mole of oxygen
when a 28.7 g sample of KI dissolves in 60.0 g of water in a calorimeter, the temperature changes from 27.2 celsius to 13.2 celsius. calculate delta H for this process. KI -----> K + I delta H=?
20,328 J
the molar volume of a gas at standard temperature and pressure is
22.4 L/mol
2C6H6 + 15O2 -----> 12CO2 + 6H2O; what volume of CO2 will be produced when 128.0 g of C6H6 reacts at STP
220
how many grams of oxygen are there in .882 moles O2
28.2
3CuSO4 + 2Al -----> Al2(SO4)3 + 3Cu; how many grams of copper will be produced from 8.25 grams of Al
29.15
what is the formula mass for BaBr2
297.1 amu
in the equation, 2KCl + 3O2 ------> 2KClO3 what is the molar ratio of potassium chloride to oxygen
2:3
in the reaction that follows, how many moles of copper will be produced from 2 moles Al? 3CuSO4 + 2Al ------> Al2(SO4)3 + 3Cu
3 mol
if 3.0L CH4 are burned according to the equation CH4 + 2O2 ----> CO2 + 2H2O, what volume of carbon dioxide will be produced at STP
3.0L
what is the freezing point depression when 85.3 of oxygen is dissolved in 1500 g of water? k for water is 1.86 C/m
3.3 C
magnesium reacts with hydrochloric acid according to the following equation: Mg + 2HCl ----> MgCl2 + H2. if .30 mole of Mg reacts, how many molecules of HCl will also react
3.6 x 10^23
the number of atoms in 24 g calcium is
3.6 x 10^23
how many moles of CO2 are found in 83.5L CO2
3.73
how many grams of I2 should be added to 750 g of CCl4 to prepare a .020 m solution
3.8 g
a 10 g mass of krypton occupies 15.0L at a pressure of 210 kPa. find the volume of the krypton when the pressure is increased to 790 kPa
3.987 L
at 25C, .42 mole of argon gas occupies 300 mL. what is the pressure, in atm of the argon gas
34.25 atm
a sample of gas occupies 17 mL at -112 degrees celsius . assuming the pressure is held constant, what volume does the sample occupy at 70 degrees celsius
36 mL
2P + 3Br2 ------> 2PBr3; if the actual yield PBr3 is 30 g, calculate the expected yield
39.47 g
what is the molar mass of NaOH
39.99 g/mol
______CuSO4 + _______Al ------> Al2(SO4)3 + Cu which of the following represents this equation balanced correctly
3CuSO4 + 2Al -----> Al2(SO4)3 + 3Cu
according to the equation that follows, how many moles of FeCl3 will be produced from 6 moles of Cl2? 2FeBr3 + 3Cl2 -------> 2FeCl3 + 3Br2
4 mol
what mass of cooper is produced when 3.8 g of iron reacts with excess copper (II) sulfate according to the equation: Fe + CuSO4 ------> FeSO4 + Cu
4.3 g
how many molecules of sucrose (C12H22O11) are there in 250 g of sucrose (C12H22O11)
4.4 x 10^23
what will dissolve the fastest under constant stirring and temperature
5 grams of granular sugar in 400 mL of water
2C6H6 + 15O2 -----> 12CO2 + 6H2O; what is the molar ratio of oxygen to water
5:2
2C6H6 + 15O2 -----> 12CO2 + 6H2O; how many moles of CO2 are produced for every 1 mole of C6H6 reacted
6
how many molecules are there in 1 mole of a compound
6.02 x 10^23
how many molecules of NO2 are found in .116 moles of NO2
6.98 x 10^22
how many grams of N20 are there in 8.21 x 10^23 molecules of N20
60.0
the specific heat of water is 4.184 J/gC. how much heat is required to change the temperature of 5.0 g of water from 21 degrees Celsius to 24 degrees Celsius
62.76 J
a gas with a volume of 4.0 L at a pressure of 205 kPa is allowed to expand to a volume of 12.0 L. what is the pressure in the container if the temperature remains constant
68.3kPa
a chemist purchases a 51.2 L cylinder of methane gas (CH4). at 285K, the pressure inside the cylinder is 1.97 atm. how many grams are in the cylinder
69.15 g
a chemist carries out the reaction of .333 moles of F2 with excess Cl2. at 200.0C and 1.08 atm, what is the maximum volume of ClF3, in liters that the reaction can produce; Cl2 + 3F2 ----> 2ClF3
7.98
a particular reaction is expected to produce 2.6L of oxygen gas. In reality, the reaction only produces 1.9L of oxygen gas. The percent yield of the reaction is
73%
2P + 3Br2 ------> 2PBr3; if the actual yield of PBr3 is 30 g and the expected yield is 39.47, what is the percent yield
76%
how many liters of N2 are found in 3.4 moles of N2
76.16
which of the following is not equivalent to the the remaining three: 760,000 Pa, 760 mm Hg, 1 atm, and 101.3 kPa
760,000 Pa
in the equation, 2KCl + 3O2 ------> 2KClO3, if the actual yield of KClO3 is 12.8 and the expected yield is 16.4, then the percent yield is
78%
the gases CO2, O2, N2, and Kr are mixed in the same container. all of the gases have the same partial pressure and the total amount of pressure of the container is 33,500 Pa. what is the partial pressure of N2
8,375 Pa
a gas has a volume of 590mL at a temperature of -55.0C. what volume will the gas occupy at 30.0C
820.04mL
how much heat is transferred when 100.0 g of (CaO) reacts with Carbon according to the reaction below? CaO + 3C -------> CaC2 + CO; delta H= 464.8 kJ
828.8 kJ
calculate the amount of heat released by the combustion of 1.75 mol of benzene (C6H6); 2C6H6 + 15O2 ------> 12CO2 + 6H2O delta H= -98.0 kJ
85.8 kJ
the equation for synthesis of ammonia is: N2 + 3H2 -------> 2NH3. how many moles of H2 are needed to produce 6 moles of NH3
9
ribosome has a molar mass of 150 g/mol and a chemical composition of 40.0% carbon, 6.67% hydrogen, and 53.3% oxygen. what is the molecular formula for ribosome
C5H10O5
the chemical formula for carbonic acid is
H2CO3
what is considered the universal solvent
H2O
the chemical formula for phosphoric acid is
H3PO4
the chemical formula for hydrobromic acid is
HBr
what is the empirical formula for a compound which contains 6.5 g potassium, 5.9 g chlorine, 8.0 g oxygen
KClO3
the chemical formula for sodium hydroxide is
NaOH
what is the formula for dalton's law of partial pressures
P(total) = P1 + P2 + P3.......
what is the formula for boyle's law
P1V1 = P2V2
what is the formula for the ideal gas law
PV = nRT
what is the formula for charle's law
V1T2 = V2T1
in a ____________ reaction, the energy released when the new bonds are formed is less than the energy required to break the old bonds
endothermic
in a _________________ reaction, heat is pulled from the surroundings into the system
endothermic
in an enthalpy diagram when the diagram rises or the reaction absorbs it is a __________ reaction
endothermic
2C6H6 + 15O2 ----> 12CO2 + 6H2O delta H = -98.0 kJ; when the amount of heat released is 85.8 kJ what is the type of reaction?
exothermic
a ____________ reaction would feel hot to touch
exothermic
in a __________ reaction, heat is released
exothermic
in a ___________ reaction experiences heat as a product
exothermic
in a ___________ reaction experiences heat moving from the system to its surroundings
exothermic
in a ______________ reaction, heat is released because the energy released in the formation of new bonds is greater than the energy needed to break the old bonds
exothermic
in an enthalpy diagram when the diagram goes down or the reaction emitts it is a _________ reaction
exothermic
when air particles are heated they
expand and rise
the amount of product that should be produced by a chemical reaction according to stoichiometric calculations
expected yield
the calculated amount of product that should be produced in a chemical reaction is called
expected yield
the sum of the atomic masses of all atoms in a compound as represented in a chemical formula; measured in amu's
formula mass
which would increase the rate at which a solid dissolves in a liquid
grinding the solid into smaller pieces
if the coefficients of a balanced equation are halved, the enthalpy change for the reaction is
halved
in an acidic molecule, the acidic hydrogens
have a slight positive charge
what is the transfer of energy from one object to the next
heat
__________ states that the solubility of a gas is directly proportional to its partial pressure
henry's law
the name of the acid HCl is
hydrochloric acid
the acid with the formula HI is
hydroiodic acid
an H^+ ion in water is more accurately described as
hydronium ion
this is formed by the addition of a proton to a water molecule; accounts for the properties of acids
hydronium ion
as the temperature of a fixed volume of a gas increases, the pressure will
increase
a substance that changes color at certain pH values and can therefore be used to roughly determine whether a sample is an acid or a base
indicator
hess's law makes it possible to
indirectly determine the enthalpy change of a reaction
if a substance is unable to dissolve in another substance it is considered to be
insoluble
an acid
is an electrolyte
the limiting reactant in a chemical reaction
is completely used up in the reaction
the Ka of a weak acid
is less than 1
the heat absorbed by reactants in an endothermic reaction
is stored in the chemical bonds of the products
if a balloon is squeezed, what happens to the pressure of the gas inside the balloon
it increases
which of the following is the SI unit for energy
joule
which of the following is the SI unit for heat
joule
the dissociation constant for a weak acid is
less than 1
substance that is completely used up in a chemical reaction and that therefore determines the maximum amount of product that can be formed
limiting reactant
the molar mass of a compound depends on the
mass of each element in the compound
to calculate how many liters of oxygen are needed to react with 10.0 grams of potassium chloride, you need to set-up and answer a _________ stoichiometry problem
mixed
the concentration of a solution determined by the number of moles of solute per kilogram of solvent
molality
the mass in grams of one mole of a substance
molar mass
the molecular formula of a compound can be determined by comparing the empirical formula mass with the
molar mass of the compound
the volume of one mole of an ideal gas at stp
molar volume
the concentration of a solution determined by the number of moles of solute per liter of solution
molarity
the quantity of a substance that has a mass in grams numerically equal to its formula mass; equal to 6.02 x 10^23 representative particles
mole
the chemical formula that indicates the numbers of each atom in a molecular compound
molecular formula
in a combustion reaction, the energy released as the products form is
more than the energy required to break apart the reactants
it is possible to convert moles to particles by
multiplying by 6.02 x 10^23
a chemical reaction between an acid and a base that destroys the distinctive properties of both; produces water and a salt
neutralization
the particles on a solution will ________ settle out
never
how many molecules of Mg(OH)2 are found in 76 g Mg(OH)2
none of these
how many moles of H2SO4 are found in in 43.4 g H2SO4
none of these
which is an endothermic reaction: 2C6H6 + 15O2 ----> 12CO2 + 6H20 delta H= -98.0 kJ CaC2 + CO ----> CaO + 3C delta H= -464.8 kJ C3H8 + 5O2 -----> 3CO2 + 4H2O delta H= -2220 kJ
none of these
in terms of dissolving substances, a ________ solvent will dissolve a _______ solute
nonpolar -nonpolar
what does the ideal gas law allow a scientist to calculate that the other gas laws do not?
number of moles
the process dissolving
occurs at the surface of the solid solute and increases with stirring
percent yield is the quantity of product actually produced compared with the quantity
of product expected
H2SO4 is considered to be
oxy
phosphoric acid is considered to be
oxy
H2SO4 is an example of a
oxy acid
in the equation 2KCl + 3O2 ------. 2KClO3, the limiting reactant when 10.0 g of KCl reacts with 4.5 g of O2 is
oxygen
the actual yield divided by the expected yield times 100 percent
percent yield
the ratio of the actual amount of product to the amount of product in a calculated chemical reaction is called the
percent yield
the mass of each in a compound relative to the total mass of the compound; found by dividing the mass of the element by the mass of the compound and multiplying the quotient by 100
percentage composition
stoichiometry problems may involve all of the following except
predicting how fast a reaction will occur
by definition, an Arrhenius acid
produces H^+ ions
by the Arrhenius definition, a base
produces an OH ion in water
the solubility of a gas dissolved in a liquid is not affected by the
rate at which the gas dissolves
an exothermic reaction
releases heat to its surroundings
an ionic compound formed from the anion of an acid and cation of a base; typically a crystalline compound with a high melting point
salt
a chemical reaction between water and the ions of a dissolved salt: may produce an acidic, basic, or neutral solution
salt hydrolysis reaction
the description of a solution that contains as much dissolved solute as it can under existing conditions
saturated
which of the following solutions is an alloy
silver in copper
if a substance is able to dissolve in another substance it is considered to be
soluble
the substance that is dissolved in a solvent to form a solution is known as
solute
the substance that does the dissolving in a reaction is known as the
solvent
the size of a temperature increase in a substance depends primarily upon the
specific heat and mass of the substance
STP stands for
standard, temperature, and pressure
the study of quantitative relationships that can be derived from chemical formulas and equations
stoichiometry
the enthalpy change for a reaction is determined by
subtracting the enthalpy of the reactants from the enthalpy of the products
the name of the acid H2SO4 is
sulfuric acid
this describes a solution that contains more dissolved solute than a saturated solution
supersaturated
what is a factor in the rate at which a substance dissolves
surface area
which is not a colligative property
temperature
in a laboratory situation, the best way to determine if a substance is an acid or a base is to
test the substance with litmus paper
as temperature of the gas in a balloon decreases, which of the following occurs
the average kinetic energy of the gas decreases
the number of moles of each substance taking part in a chemical reaction is indicated by
the coefficients in the balanced equation
a balanced equation verifies the law of conservation of matter because
the mass of the reactants equals the mass of the products
the standard state of an element is defined as
the most form of the element under standard conditions
what happens to the pressure of a gas inside a container if the temperature of the gas decreases
the pressure decreases
why does air escape from a tire when the tire valve is opened
the pressure outside the tire is lower than they pressure inside the tire
if the volume of a container of gas is reduced, what will happen to the pressure inside the container
the pressure will increase
if sun range a has a keq of .67 and substance b has a keq of .92 then
the substances are not dissociating because their keq values are less than 1
what happens to the temperature of a gas when it is compressed
the temperature increases
which of the following changes would cause a decrease in the pressure of a contained gas
the volume of the container is increased
why does the pressure inside a container of gas increase if more gas added to the container
there is an increase in the number of collisions between particles and the walls of the container
which statement about enthalpy is not true
there is generally a very large numerical difference between the energy and the enthalpy of a substance
a strong acid
transfers H^+ to water to form H3O^+
the describes a solution that contains less dissolved solute than it can under existing conditions
unsaturated
which of the following is not a step in solving mass-mass problems
use the mass ratio to determine the grams of the substance sought
which is an example of a polar solvent
water
a gas occupies 900.0 mL at a temperature of 27.0C. what is the volume at 132.0C
1215 mL
1 nutritional Calorie is equivalent to
1000 calories
how many grams of KNO3 should be used to prepare 2.00L of a .500 M solution
101 g
how many grams of ammonia (NH3) are there in 15.8L NH3
12.0
which of the following is the correct formula for calculating percent yield
(actual/expected) x 100
2P + 3Cl2 ------> 2PCl3; delta H= -640 kJ 2P + 5Cl2 ------> 2PCl5; delta H= -886 kJ calculate delta H for the reaction PCl3 + Cl2 -----> PCl5
-123 kJ
how much heat will be released if 9.75 g of aluminum reacts with excess ammonium nitrate (NH4NO3) according to the equation: 2Al + 3NH4NO3 ------> 3N2 + 6H2O + Al2O3; delta H= -2030 kJ
-366 kJ
when a 16.9 g sample of NaOH dissolves in 70.0 g of water in a calorimeter, the temperature changes from 22.4 degrees celsius to 86.6 degrees celsius. calculate delta H for this process. NaOH ------> Na + OH delta H= ?
-44.5 kJ
what is the mole fraction of SO2 in an industrial exhaust gas containing 128.0 g of SO2 dissolved in every 1500 g of carbon dioxide
.055
a gas mixture contains the following gases with the mole fractions indicated: N2 (.450), O2 (.334), CO2 (.023), SO2 (.017), and N2O4 (.120). the mixture also contains the gas argon. what is the mole fraction of argon
.056
what is the molarity of a solution in which 10.0 g of AgNO3 is dissolved in 500 mL of solution
.118 M
what is the specific heat of gold if the temperature of an 8.21 g sample of gold is increased by 6.2 Celsius when 6.51 J of heat is added
.13 J/gC
what is the molarity of a .75 L solution containing 9 g of NaCl in water
.21 M
what is the molality of a solution in which 25g of NaCl is dissolved in 2000 g of water
.21 m
a salt shaker filled with 17.0 g sodium chloride contains ___________ mol NaCl
.291
a gas mixture contains 50.4 g of dinitrogen monoxide (N2O) and 65.2 of oxygen gas. what is the mole fraction of N2O
.360
if a gas occupies a volume of 2.4L at 14.1 kPa. what volume will the gas occupy at 84.6 kPa
.4 L
how many moles are there in 22.4L of a gas
1
what is the molarity of a solution in which 58 g of NaCl are dissolved in 1.0 L of solution
1.0 M
3CuSO4 + 2Al -----> Al2(SO4)3 + 3Cu; how many moles of copper will be produced from .75 moles of Al
1.125 mol
how many moles of oxygen are there in 9.25 x 10^23 molecules of O2
1.54
how many moles of Mg are found in 38.6 g of Mg
1.59
what is the boiling point of elevation when 11.4 g of ammonia (NH3) is dissolved in 200 g of water? k for water is .52 C/m
1.7
at 108,231 Pa and 45C, what is the density, in g/L of 1 mole of CO2
1.8 g/L
Ca(OH2) is considered to be
a base
sodium hydroxide is considered to be
a base
the bronsted-Lowry definition for acids and vases states that
a base accepts H^+ ions and a base is a proton acceptor
the reaction of a string acid and weak base in water produces
a slightly acidic salt solution
which is true
a solution that contains electrolytes conducts electricity
HC2H3O2 is the chemical formula for the compound
acetic acid
according to the bronsted-Lowry definition, a compound that donates a proton, or H3O^+ ion
acid
if acid a has a keq of 1.07, acid b has a keq of 1.81, and acid c has a keq of 1.25 which is the strongest
acid b
indicates the strength of an acid; derived from the equilibrium constant for the acids dissociation in water
acid dissociation constant
the salt solution formed from a strong acid and a weak base is
acidic
a hydrogen atom that an acid may lose as an H3O^+ ion
acidic hydrogen
the amount of product obtained from a chemical reaction
actual yield
the particles in a solution
all of these (are small, are evenly distributed, will not separate out of solution)
which are forms of a solution
all of these (lemonade, air, ocean water)
a weak acid
all of these (reacts with water only partially to form H3O^+ ions, has a strong conjugate base, and has a Ka less than 1
in a neutralization reaction
all of these are correct (the base in the reaction is neutralized, the acid in the reaction is neutralized, a salt is formed)
a _______ is a solid solution in which the atoms of two or more metals are uniformly mixed
alloy
a substance that can act as an acid or a base is
amphoteric
the description of any substance that can react as either an acid or a base
amphoteric
the combustion of glucose in your body is
an exothermic reaction
the weighted average of the masses of the existing isotopes of an element
atomic mass
the number of atoms in one mole of an element is equal to
avogadro's number
the number of representative particles in one mole: 6.02 x 10^23
avogadro's number
according to the bronsted-Lowry definition, a compound that accepts a proton, or H3O^+ ion
base
indicates the strength of a base; derived from the equilibrium constant for the base's dissociation in water
base dissociation constant
HCl is considered to be
binary
hydrobromic acid is considered to be
binary
which is an alloy
brass
2P + 3Br2 ------> 2PBr3; if 5 g of phosphorous and 35.0 g of bromine mix, which is the limiting reactant
bromine
Ca(OH2) is the chemical formula for the compound
calcium hydroxide
according to the _________ theory, early scientists thought that heat was a kind of _________
caloric - liquid
Carbonic acid is considered to be
carboxylic
HC2H3O2 is considered to be
carboxylic
an electrolyte
carries an electric current in solution
boiling point elevation is a colligative property that
changes the boiling point of a solution
a strong acid in a water solution is
completely ionized
an acid formed when a Brønsted-Lowry base gains a proton
conjugate acid
a base formed when a Brønsted-Lowry acid loses a proton
conjugate base
a saturated solution
contains the maximum amount of solute that can be dissolved
which are methods for determining the concentration of a solution
determining molarity and determining molality
the chemical formula that gives the simplest whole-number ratio of atoms of elements in a compound
empirical formula
CaO + 3C -------> CaC2 + CO; delta H= 464.8 kJ; when the amount of heat transferred is 828.8 kJ what is the type of reaction?
endothermic
a ____________ reaction would feel cold to touch
endothermic
in a ___________ reaction experiences heat is needed to start the reaction
endothermic
in a ___________ reaction, heat is absorbed
endothermic
