39 Results
The Rate Equation   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
The Rate of Reaction   
(Other (1))
A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
Relative Reactivity: Strong Acid, Weak Acid, Buffer Solution   
(Movie/Animation, Audio/Visual (8))
A strong acid, a weak acid, and a buffer solution are each added to sodium bicarbonate and the reaction rates are compared.
Oscillating Reaction: Belousov-Zhabotinskii - Time-Lapse   
(Movie/Animation, Audio/Visual (7))
Time-lapse versions of the Belousov-Zhabotinskii reaction taking from 10 to 60 seconds are presented.
Iodine Clock Reaction   
(Movie/Animation, Audio/Visual (6))
A solution of hydrogen peroxide and sulfuric acid is added to a solution containing iodide ion, thiosulfate ion, and starch. After some time the dark blue color of a triiodide-starch complex is observed. The influences of initial reactant concentrations on the reaction time are examined, as are the influence of volume and temperature.
Rates of Reactions   
(Movie/Animation, Audio/Visual (6))
The effects of a variety of variables, including concentration, temperature and catalysts, on reaction rate are shown.
Energy from Oxidation of Food   
(Movie/Animation, Audio/Visual (4))
Food undergoes rapid oxidation when placed in molten potassium chlorate.
Halting the Briggs-Rauscher Oscillating Reaction   
(Movie/Animation, Audio/Visual (4))
The Briggs-Rauscher reaction is demonstrated in three different ways. Catalase from a liver extract decomposes the hydrogen peroxide in an Briggs-Rauscher reaction, stopping the oscillations.
Factors Affecting Glucose Oxidase Activity   
(Movie/Animation, Audio/Visual (4))
Various factors which affect glucose oxidase activity are demonstrated.
Oscillating Reaction: Briggs-Rauscher   
(Movie/Animation, Audio/Visual (3))
When a solution of malonic acid, starch, and manganese(II) ion is added to a solution of hydrogen peroxide, iodate ion, and sulfuric acid, gas bubbles form and the color of the resulting mixture oscillates periodically from colorless to amber to blue.
Oscillating Reaction: Belousov-Zhabotinskii   
(Movie/Animation, Audio/Visual (3))
Belousov-Zhabotinskii reactions are shown both as movies and as stills.
Induction by Iron(II) of the Oxidation of Iodide by Dichromate   
(Movie/Animation, Audio/Visual (2))
Acidic aqueous solutions containing dichromate and iodide ions are mixed with no reaction. The addition of a solution of iron(II) ion induces the rapid formation of brown triiodide ion.
Blue Bottle, Red and Blue Bottle   
(Movie/Animation, Audio/Visual (2))
Color changes are caused by reactions of oxygen in the air with chemicals in a solution. The colors fade over time, but can be regenerated by shaking the flask containing the solution.
Enthlapy-Thermodynamics   
(Movie/Animation, Audio/Visual (10))
Reactions and demonstrations the explore thermodynamic concepts.
Kinetics : ElementRxnRateLaws (13 Variations)   
(Assessment Material (1))
Assume that the equation below represents an elementary reaction. Predict the rate expression (rate law) for this reaction.

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

Kinetics : RxnMechanisms (14 Variations)   
(Assessment Material (1))
Experiments show that the reaction of nitrogen dioxide and carbon monoxide
NO2 + CO NO + CO2

has the following rate expression at high temperatures:

Rate=k[NO2][CO]

Is the following mechanism compatible with the experimental information?
(1) NO2 + CO O-N-O-C-O (slow)
(2) O-N-O-C-O NO + CO2 (fast)
Choose the best answer.

Kinetics : RxnOrder (10 Variations)   
(Assessment Material (1))
For the reaction below, determine the order with respect to each reactant and the overall order.
2NO2(g) + F2(g) 2NO2F(g)
rate = k[NO2][F2]
Kinetics : InitialRateMethod (16 Variations)   
(Assessment Material (1))
Use the experimental data below to determine the rate equation for the following reaction.


Kinetics : IntegratedRateLaw (6 Variations)   
(Assessment Material (1))
The following kinetics information may be useful in answering this problem.

Use the plots below to determine the order of the reaction with respect to A.



Kinetics : RateLawChangeConc (10 Variations)   
(Assessment Material (1))
The rate law for a reaction is rate=k[A][B]. If the concentration of A doubles, the rate of the reaction will do which of the following?
Kinetics : IntermediateInMech (15 Variations)   
(Assessment Material (1))
Suppose that for the reaction of nitrogen dioxide and carbon monoxide
NO2 + CO NO + CO2

the following mechanism has been proposed at high temperatures:
(1) NO2 + CO O-N-O-C-O (slow)
(2) O-N-O-C-O NO + CO2 (fast)
Check the box for each species that is an intermediate in this mechanism.

Kinetics : ElementaryRxnOrNot (9 Variations)   
(Assessment Material (1))
Which of the following reactions could be elementary and unimolecular reactions?
Kinetics : RateConstantUnits (8 Variations)   
(Assessment Material (1))
The isomerization of CH3NC to CH3CN has a rate constant of 0.46 s-1 at 600 K.

(1) Based on the units of the rate constant, what is the order of the reaction? {1:MULTICHOICE:zero-order#No, that is not correct.~=first-order#Correct!~second-order#No, that is not correct.~third-order#No, that is not correct.}

(2) What is the concentration of CH3CN after 0.20 minutes of reaction if the initial concentration is 0.10 M? {1:NUMERICAL:=4e-4:1e-5#Correct!~%50%4e-4:5e-5#Close, but not quite.}(Do not include units!)

Kinetics : InterpretEnergyProfile (16 Variations)   
(Assessment Material (1))
Use the energy profile below to decide if the following statements are true or false.
Kinetics : ExpDataRateConst (16 Variations)   
(Assessment Material (1))
Use the experimental data below to determine the rate constant for the following reaction.


Equilibrium : EquilAndRxnRates (8 Variations)   
(Assessment Material (1))

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

Kinetics : CatalyticConverters (4 Variations)   
(Assessment Material (1))
The following table illustrates the changes in emissions requirements for automobiles:
Pollutant1970 Emissions1990 EmissionsCA ultra-low emissions
CxHy1.5 g/mile0.25 g/mile0.04 g/mile
CO15 g/mile3.4 g/mile1.7 g/mile
NOx3.1 g/mile0.4 g/mile0.2 g/mile
Catalytic converters are used in automobiles to convert pollutants in engine emissions to benign products. Catalytic converters in today's automobiles are made of a porous ceramic brick that has been coated with catalysts, additives, stabilizers, and support materials. Corning has developed bricks that have very thin-walled channels with 600 channels per square inch. Which of the following research goals did they target?
Kinetics : CatalystTrueFalse (7 Variations)   
(Assessment Material (1))
Check the box for each statement about catalysts that is true.
Kinetics : ArrheniusTemp (3 Variations)   
(Assessment Material (1))
The activation energy for the isomerization of cyclopropane to propene is 274 kJ/mol. By what factor does the rate of reaction increase as the temperature rises from 500oC to 550oC assuming all else remains constant? (R = 8.314 J/mol k)

Hint: This is asking for the ratio of rates which is proportional to the ratio of the rate constants, all else being equal.

Kinetics : ArrheniusRateConst (4 Variations)   
(Assessment Material (1))
CH3CH2NO2 C2H2 + HNO2

Using the graph below, calculate the rate constant for this reaction at 40.0oC.

Kinetics : ArrheniusActEnergy (4 Variations)   
(Assessment Material (1))
The rate constant for the first-order dehydration of tert-butyl alcohol at 500oC is 1.20 x 10 -4 s -1. The rate constant for this process at 600oC is 6.80 x 10 -3 s -1. Calculate the activation energy for this reaction in kJ/mol. (R = 8.314 J/mol K)
Kinetics : Enzyme (7 Variations)   
(Assessment Material (1))
Trypsin assists in digestion by breaking proteins down into smaller peptides. However, this process is not as efficient in the presence of fluorophosphates. Identify the role of each of these components.
Kinetics : RxnProfileEaDeltaE (11 Variations)   
(Assessment Material (1))
Based on the reaction profile, what is the energy change for the reaction?
Kinetics : FactorsAffectingRate (7 Variations)   
(Assessment Material (1))
Which of the following changes would NOT affect the rate of the reaction of cisplatin with water?
Pt(NH3)2Cl2(aq) + H2O(l) [Pt(NH3)2(H2O)Cl]+ + Cl-
Kinetics : CompareEnergyProfile (11 Variations)   
(Assessment Material (1))
Consider the following reactions that take place at the same temperature, begin with the same molar concentrations, and whose energy profiles are presented below:
Kinetics : ConcVsTimeGraph (8 Variations)   
(Assessment Material (1))
The following graph shows the change in concentration as a function of time for the reaction:
2NO2(g) + F2(g) 2NO2F(g)
What do each of the curves A, B, and C represent?
ChemPaths 104 M Feb 21   
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Today in Chem 104: * Lecture: Rate Laws * Reading: Kotz:, Ch. 15, Sec. 3-4 Moore, Ch. 13, Sec. 3-5 * Homework #5 due by 11:55 pm F Feb 25 * Excel assignment due in first discussion section this week * Quiz 4 in second discussoin section
The Rate of Reaction in Everyday Life   
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A section of ChemPrime, the Chemical Educations Digital Library's free General Chemistry textbook.
ChemPaths 104 F Feb 18   
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Today in Chem 104: * Lecture: Rates of Reaction * Reading: Kotz: Ch. 15, Sec. 1-2 Moore, Ch 13, Sec. 1-2 * Homework #5 due by 11:55 pm F Feb 26 * Excel Assignment due at first discussion section next week (week of Feb. 21)