TIGER

Assessment Questions: 40 results
Intermolecular_Forces__Liquids_and_Solids : VaporPressure (10 Variations)
Which of the following statements is true?
Noncovalent Interactions
Gases : GasGramMixPressure (5 Variations)
4.80 g of CH4 is mixed with 17.6 g of CO2 in a 9.00 L flask at a temperature of 67.2oC. What is the total pressure of the flask? (Assume there is no reaction.)
Gases |
Chemometrics
Gases : GasMoleMixPressure (5 Variations)
What is the pressure exerted by a mixture of gases in a 40.0 L container at 127oC if the mixture contains 0.100 mol O2, 0.400 mol CH4, and 0.500 mol SO2?
Gases |
Chemometrics
Solutions : ReverseOsmosis (20 Variations)
You are given a water sample that contains ammonium chloride (NH4Cl). You determine the concentration of the salt to be 0.500 M and decide to purify the water using reverse osmosis. What is the minimum pressure that must be applied at 30.0oC to force the water through the membrane?
Solutions / Solvents |
Transport Properties
Thermochemistry : PhaseChangeEnthalpy (10 Variations)
A solid melts to a liquid. Which of the following statements are true? (Assume constant pressure and a flexible container.)
Calorimetry / Thermochemistry |
Phases / Phase Transitions / Diagrams
Equilibrium : SolubilityPressTemp (16 Variations)
How does increasing the temperature change the solubility of nitrogen in water?
Equilibrium
Gases : GasLaws (2 Variations)
Note: This is a calculation type question. If you exit the quiz without submitting it and you do not save an answer before exiting the quiz, the values in the question may change when you enter the quiz again.

You purchase a propane tank that can hold gas safely up to a pressure of {x} atm. When the tank contains 100. grams of propane at {y}°C, the gas exerts a pressure of {z}atm. What is the highest temperature to which the propane can be heated safely? (Report your answer in Kelvins.)

Gases |
Chemometrics
Bonding : ImpossibleStructure (10 Variations)
Which of the following formulas represent substances that are likely to be stable at ordinary temperature and pressure? A good way to decide is to ask for which of the formulas is it possible to draw a reasonable Lewis structure (one that obeys the usual rules for drawing Lewis structures)?
Lewis Structures |
Covalent Bonding
Equilibrium : CalcKp (2 Variations)
In one experiment chemists studied the formation of phosgene, COCl2, by mixing {y} atm of carbon monoxide and {z} atm of Cl2 in a reaction vessel at 700K. After the system reached equilibrium, the total pressure was {x} atm. Calculate Kp for the reaction.

Hint: Remember that the total pressure is the sum of all the partial pressures.

Note:
      Do Not use scientific notation
      DO NOT use spaces
      DO NOT write in the units.
      Be sure to write your answer with only one decimal place even if this is not the correct number of significant figures.

Equilibrium |
Chemometrics
Gases : GasRxnVolumes (10 Variations)
A gas phase reaction takes place in a syringe at a constant temperature and pressure. If the initial volume before reaction is 30 mL and the final volume after the reaction is complete is 15 mL, which of the following reactions took place? (Note: You can assume that you start with stoichiometric amounts of the reactants, the reaction goes to completion and that the gases behave ideally.)
Gases |
Chemometrics
Gases : OzoneMolcsFromppm (10 Variations)
Although ozone is an important component of the upper atmosphere, long-term exposure to ozone in the air we breathe can cause inflammation of the lung, impairment of lung defense mechanisms, and irreversible changes in lung structure. The EPA has set an 8 hour limit for ozone of 0.08 ppm as an air quality standard for cities. At the EPA limit, how many ozone molecules are present in 5.0 liters of air at 25oC and 0.967 atm? (Hint: assume that air is an ideal gas and calculate the total number of molecules there are in 5.0 L. Then use the definition of ppm.)
Gases |
Chemometrics
Gases : GasRxnStoich (10 Variations)
One of the reactions in the process of obtaining very pure silicon for the microelectronics industry is shown below. If 24 g of SiO2 is reacted with an excess of carbon, what volume of gaseous carbon monoxide will be produced at a temperature of 17oC and a pressure of 735 mm Hg?

SiO2(s) + 2C(s)Si(S) + 2CO(g)


Gases |
Chemometrics
Equilibrium : ConvertKcKp (6 Variations)
Nitrosyl bromide is formed from nitrogen oxide and bromine:

Kp for this reaction is {x} at {y}°C. Calculate Kc at this temperature. (R = 0.0821 L atm/mol K)

Note:
DO NOT use scientific notation
Use integers (no decimal places) even is this is not the correct number of significant figures.
DO NOT write in the units.
eg: 18


Equilibrium |
Chemometrics
Thermochemistry : CalcMolarEnthalpy (5 Variations)
White phosphorus, P4, ignites in air to produce heat, light, and P4O10 according to the following reaction.

P4(s) + 5O2(g) P4O10(s)

If 67.2 g of P4 is burned,1620 kJ of energy is evolved. What is the molar enthalpy of combustion of P4 if the process was carried out under constant pressure?


Calorimetry / Thermochemistry |
Chemometrics
Equilibrium : EquilTrueFalse (4 Variations)
Which of the following statements is a true statement concerning a reaction that has reached a state of equilibrium?
Equilibrium
Equilibrium : KspExpressions (10 Variations)
What is the solubility product expression for Ag3PO4?
Equilibrium
Equilibrium : KspSaturation (12 Variations)
Zn(OH)2 has a Ksp of 4.5 x 10-17. If you have a solution of Zn(OH)2 that has a hydroxide ion concentration equal to 4.6 x 10-6 mol/L, the solution is ... (Assume that the only relevant reaction is the solubility-product equilibrium.)
Equilibrium
Equilibrium : LeChatPrinciple (18 Variations)
Consider the following equilibrium, established in a 2 L flask at 30oC.

CO(g) + H2O(g) CO2(g) + H2(g) H0= -41.2 kJ

What will happen to the concentration of CO2 if the temperature is increased?


Equilibrium
Equilibrium : RxnDirectAndTemp (16 Variations)
2 SO2(g) + O2(g) 2 SO3(g)
The reaction above has an equilibrium constant of 0.25 at 830oC, and Horxn = -197.78 kJ/mol under standard conditions. Under which conditions will this reaction produce the most sulfur trioxide?

Equilibrium
Equilibrium : EquilExpressions (15 Variations)
What is the correct equilibrium constant expression for the balanced reaction shown below?

C3H8(g) + 5O2(g) 3CO2(g) + 4H2O(l)


Equilibrium
Equilibrium : InterpretEqConsts (12 Variations)
The following reaction has an equilibrium constant of 1.2x1018 at 25oC.

CH4(g) + Cl2(g) CH3Cl(g) + HCl(g)

Which of the following statements is true?


Equilibrium
Equilibrium : ICETables (16 Variations)
2C2H2(g) + 5O2(g) 4CO2(g) + 2H2O(g)

You have 0.4 moles C2H2 and 0.2 moles O2 present initially in a 5L flask. You allow the reaction to run until it reaches equilibrium. Which of the following is the correct ICE table for this process?


Equilibrium
Equilibrium : CommonIonEffect (9 Variations)
The molar solubility of lead(II) fluoride (PbF2) is 2.1 x 10-3 mol/L in pure water at 25oC. What is the molar solubility of lead(II) fluoride in 0.10 M NaF at 25oC? (Assume that the only relevant reaction is the solubility-product equilibrium.)
Equilibrium |
Chemometrics
Equilibrium : ConcFromKsp (8 Variations)
The Ksp of BaF2 is 1.7 x 10-6 mol/L in water at 25oC. What is the concentration of barium ions in equilibrium with solid barium fluoride? (Assume that the only relevant reaction is the solubility-product equilibrium.)
Equilibrium |
Chemometrics
Equilibrium : InterpretKsp (16 Variations)
Which of the following salts would give you the highest concentration of phosphate ions in solution if you placed 1 mole of the salt in a liter of water?
Equilibrium |
Chemometrics
Equilibrium : EquilAndRxnRates (8 Variations)

For the reaction of A B, which of the following statements about the rates of forward and reverse reactions is true at time x?

Equilibrium |
Kinetics
Equilibrium : EqConstRelationships (12 Variations)
The equilibrium constant for the reaction of hydrogen gas and ethene to produce ethane under certain conditions is 9.8 x 1018.
H2(g) + C2H4(g) C2H6(g) K = 9.8 x 1018

What is the equilibrium constant for the following reaction under the same conditions?
C2H6(g) H2(g) + C2H4(g) K = ?


Equilibrium |
Chemometrics
Equilibrium : CalcMolesAtEquil (15 Variations)
The following reaction has an equilibrium constant of 0.083 at 900oC.

COCl2(g) CO(g) + Cl2(g)

If you have 1.00 mole of COCl2(g) in a 1.00L container initially, how many moles of COCl2 will be present when the system reaches equilibrium?


Equilibrium |
Chemometrics
Equilibrium : EqConstConcData (4 Variations)
SbCl5(g) SbCl3(g) + Cl2(g)

You have 0.50 mol SbCl5 present initially in a 1.0L flask. The system is allowed to reach equilibrium at 450oC. There is 0.10 mol Cl2 present at equilibrium. What is the equilibrium constant, K?


Equilibrium |
Chemometrics
Equilibrium : CalcRxnQuotient (13 Variations)
In an experiment, 4.44 mol of SO2, 7.93 mol of O2 and 4.03 mol of SO3 are placed in a 2.0L reaction vessel at a certain temperature. Calculate the reaction quotient, Q, for the reaction as written:

What is the calculated reaction quotient, Q? {2:NUMERICAL:=2.1e-1:1e-2#Correct! ~%50%2.1e-1:5e-2#Close but not quite right}

If Kc for this reaction at the temperature of the experiment is 3.7 x 103, will the reaction move toward the left or toward the right? {1:MULTICHOICE:left#Sorry, that's wrong.~=right#Correct!}


Equilibrium |
Chemometrics
Equilibrium : CalcKc (4 Variations)
A container initially has {y} M ammonia at a certain temperature. When the system reaches equilibrium the concentration of ammonia is {x} M. Calculate Kc for the following reaction as written.

Note:
      Answers must be written using scientific notation with "e"
      DO NOT use spaces
      DO NOT write in the units.
      Be sure to use three significant figures.
          eg:       2.44e-5

Equilibrium |
Chemometrics
Equilibrium : MoreMolesAtEquil (19 Variations)
The following reaction has an equilibrium constant of 0.050 at a given temperature.

N2(g)+ O2(g) 2NO(g)

If you have 0.75 moles of N2(g) and 0.75 moles of O2(g) in a 2.0L container initially, how many moles of N2 will be present when the system reaches equilibrium?


Equilibrium |
Chemometrics
Acids_and_Bases : PercentDissociationKa (3 Variations)
Calculate the percent dissociation in a {x}M aqueous solution of the weak acid HA. (Ka = {y} x 10-4)

Enter your answer to ONE decimal place.
DO NOT use scientic notation.
DO NOT write in the units.


Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
Equilibrium
Acids_and_Bases : WeakAcidSolnpH (20 Variations)
Given an aqueous solution of 0.30 M acetic acid (Ka = 1.8 x 10-5), the pH is approximately ...
Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : BufferingCapacity (20 Variations)
If a buffer is prepared using 0.75 mol CH3COOH and 0.45 mol CH3COO- in 1 liter of aqueous solution, is the buffering capacity of the solution great enough to maintain its pH if 10 g NaOH is added?
Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : pHDilution (6 Variations)
What is the pH of a solution made by diluting {x} mL of {y} M HNO3(aq) to a total volume of 500 mL?

Enter your answer to two decimal places.
DO NOT use scientific notation

Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : pHBufferCalc (4 Variations)
Calculate the pH of a buffer solution containing {x}M NH3 and {y}M NH4NO3.

Enter your answer to TWO decimal places.
DO NOT use scientific notation.
DO NOT enter units
        eg:     4.55

Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : BufferWeakStrong (7 Variations)
How many mL of a 2.50 M HCl solution must be added to 500 mL of a 0.150 M CO32- solution to make a buffer with pH = 10.00?
Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : CalcSolnpH (5 Variations)
Use this acid/base table to answer the question below.

Calculate the pH of a {x}M sodium acetate solution.

DO NOT use scientific notation
Enter your answer to two decimal places.
DO NOT enter units

Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium
Acids_and_Bases : BufferWeakWeak (14 Variations)
What mass of potassium bicarbonate (KHCO3) must be added to 500 mL of a 0.200 M carbonic acid solution to make a buffer with pH = 6.30?
Acids / Bases |
Reactions |
Aqueous Solution Chemistry |
pH |
Equilibrium