Rate of Reactions

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Questions

• How do you calculate rate of reaction?
• How can rate of reaction be affected?
• How can rate of reaction be increased?
• How can temperature affect reaction rate?
• How can the rate of reaction be calculated from a graph?
• How do reaction rates give information about mechanisms?
• What is a reaction rate constant?
• How do the reaction rates change as the system approaches equilibrium?
• Why does the rate of reaction increase with concentration?
• Why do rates of reaction change with pH?
• Why is the rate of reaction slow at low temperatures?
• When is a rate of reaction negative?
• Why is the rate of reaction important in industry?
• Why is the rate of reaction fastest at the beginning?
• Why does the rate of reaction change with the energy of collisions?
• Why does the rate of reaction decrease with time?
• What are the rate of reaction units?
• How can I calculate the rate of reaction from a graph?
• How does the rate of reaction change when reactants mix?
• How does the rate of reaction change with concentration?
• How does the rate of reaction affect the surface area?
• How does the rate of reaction affect activation energy?
• How does pressure affect rate of reaction?
• How do rates of reaction apply to daily life?
• How do enzymes affect rate of reactions?
• How can the rate of reaction be decreased?
• How can rates of reactions be measured?
• How can the rate of reaction be changed?
• Explain rate of reaction using collision theory?
• How can I calculate the rates and order in the following reaction? #H_2 + Br_2 -> 2HBr#
• How can I calculate the rates and order in the following reaction? H2 + I2 = 2 HI
• What is an example of a rate of reactions practice problem?
• How can a spectroscopic measurement be used for rates of reactions?
• What are some examples of rates of reactions?
• What are some laboratory methods for determining the rate of reactions?
• Question #85630
• Question #45e35
• Question #316f1
• Question #8a4f6
• Question #59e58
• Question #31a3d
• Using the equation #(d[NO_3^(-)])/(dt) = k_1[NH_4^(-)]# calculate the predicted half-life of #"NH"_4^(-)# if the initial concentration is 2600 ppm?
• Question #4cb27
• For the oxidation of ammonia it was found that the rate of formation of N2 was 0.27 mol L–1 s–1. 4NH3+3O2→2N2+6H2O At what rate was water being formed?
• Question #28434
• Question #0e8e6
• Question #0b94b
• Question #1f772
• How do you use the steady state approximation to determine the observed rate constant for an overall reaction, when knowing its mechanism and its individual rate constants?
• How do you look at a #v_0# vs. #[S]# curve (#S = "substrate"#) to find the first-order and zero-order regions? How do you find #v_(max)# and #K_M# from this curve?
• How does the temperature affect the rate of chemical reaction??
• How do enzymes alter the rate of chemical reactions?
• What is meant by the rate of a reaction?
• Question #1465c
• How does increase in concentration affect the rate of a chemical reaction?
• A first order reaction has a half life of 27.5 minutes. If the initial concentration of the reactant is 0.400 M, when will the concentration drop to 0.100 M?
• If the reaction is first order in #A# and second order in #B#, what is the rate constant if #[A] = "0.40 M"# and #[B] = "0.14 M"#?
• The reaction A+2B →products , was found to have the rate law , rate= k[A][B]². Predict by what factor the rate of reaction will increase when the concentration of A and B is doubled?
• A second order reaction is 40% completed after one hour. What is the rate constant for this reaction?
• The reaction between propanone,iodine and hydrochloric acid is a first order with respect to H+ ions. When[H+]=0.1M ,the rate is 0.865M/s. What is the rate when [H+] = 0.5 M?
• How is it possible that a catalyst without taking part in a chemical reaction increases the speed of the chemical reaction?
• What can decrease the activation energy needed to start a reaction?
• #(1)# T/F Do all lipids have a hydrophilic head and hydrophobic tail? #(2)# How is a rate constant related to the Gibbs' free energy of activation, #DeltaG^‡#?
• What happens to the reaction rate as a reactant gets used up?
• What would happen to the rate of a reaction with rate law #rate = k[NO]^2[H_2]# if the concentration of #H_2# were halved?
• What effect does temperature have on reaction rate?
• For first degree equation , time for 75% completion of reaction is X times half time of that reaction , where X is ?
• Question #07304
• Question #d6c6a
• How do rates of chemical weathering change as temperature increases?
• Question #68ca2
• Find the rate constant for parallel or competitive reactions?
• If sucrose gets hydrolyzed by water to yield two equivalents of #"C"_6"H"_12"O"_6#, what is the rate law? How should you describe the molecularity, and why is the concentration of sucrose not needed to describe the rate (provided there is excess water)?
• Question #5f1ce
• Question #8cdfb
• Question #d31d8
• For the overall reaction shown below with a fast equilibrium, why is the true rate law NOT #r(t) = k_2[A][B_2]#? Also, why is the overall reaction order #3//2# and not #3#?
• Question #4ce8a
• Question #2f466
• What would happen to the rate of a reaction with rate law rate = #k[NO]^2[H_2]# if the concentration of #NO# were doubled?
• What effect do concentration changes have on the reaction rate?
• What causes the concentration of reactants to affect the reaction rate?
• What makes an increase in temperature change the reaction rate?
• Question #9439b
• Question #a42c0
• Question #0c6cd
• Question #a2fab
• Question #23eaf
• Question #90ead
• A first order reaction has an Arrhenius constant for the reaction is #9.9 xx 10^10 sec^ -1#, and an activation energy of #"62.0 kJ"#. At what temperature (in Celsius) is the rate constant equal to #0.434 sec^-1#?
• According to the Arrhenius equation, how does temperature affect the rate constant?
• Given an activation energy of 15 kcal/mol, how do you use the Arrhenius equation to estimate how much faster the reaction will occur if the temperature is increased from 100 degrees Celsius to 120 degrees Celsius? R = 1.987 cal/(mol)(k).
• How do you find A and Ea using the Arrhenius equation?
• What is the rate constant for this first-order decomposition at 325°C? If the initial pressure of iodoethane is 894 torr at 245°C, what is the pressure of iodoethane after three half-lives?
• The rate constant for the reaction 2 C (g) -> D (g) is #0.231 s^-1# at 2°C and #11.6 s^-1# at 77°C. What is the the value of A in the Arrhenius equation?
• A second-order reaction has a rate constant of 0.007500/(M · s) at 30°C. At 40°C, the rate constant is 0.05800/(M · s). The activation energy is 161.23 kJ/mol. What is the frequency factor, A?
• What is the Arrhenius equation?
• How do you solve for k using the Arrhenius Equation? A first order reaction has an activation energy of #"E"_a = "65.7 kJ/mol"# and a frequency factor (pre-exponential factor, #"A"#) of #1.31 xx 10^12 "s"^(-1)#. Calculate the rate constant at #19^@ "C"#.
• The rate constant of a first order reaction is #4.60 xx 10^(-4) "s"^(-1)# at #350^@ "C"#. If the activation energy is #"104 kJ/mol"#, what is the temperature at which the rate constant is #8.80 xx 10^(-4) "s"^(-1)#?
• In the arrhenius equation, #k = Ae^(-E_a"/"RT)#, what is the frequency factor?
• How do you calculate the pre-exponential factor from the Arrhenius equation?
• The activation energy of a certain reaction is 46.6 kj/mol. At 20 degrees Celsius the rate constant is #0.0130s^-1#. At what temperature would this reaction go twice as fast (T2)?
• The rate constant, #k#, for a particular reaction is #1.3xx10^(-4)"M"^(-1)"s"^(-1)# at #100^@"C"# and #1.5xx10^(-3)"M"^(-1)"s"^(-1)# at #150^@"C"#. What is the #E_a# (in kJ) for this reaction?
• The activation energy of a certain reaction is 49.4 kJ/mol. At 20 degrees C, the rate constant is .0130 s^-1. What is the rate constant at 100 degree C?
• The activation energy of a certain reaction is 35.3 kJ/mol. At 20 degrees C, the rate constant is #0.0130 s^-1#. At what temperature would this reaction go twice as fast? please help?
• How do you solve the Arrhenius equation?
• How do you plot the Arrhenius equation?
• When is the Arrhenius equation used?
• What is the Arrhenius equation and what is meant by activation energy?
• How do you determine A in the arrhenius equation?
• How do you find A in Arrhenius equation?
• How do you rearrange Arrhenius equation for activation energy?
• How do you solve the Arrhenius equation for activation energy?
• How do you solve the Arrhenius equation for #T_2#?
• What does the Arrhenius equation calculate?
• Why is the gas constant in the Arrhenius equation?
• How can you tell that catalase has been added to hydrogen peroxide?
• Does every collision between reacting particles lead to products?
• Suppose a thin sheet of zinc containing 0.2 mol of the metal is completely converted to zinc oxide, #"ZnO"#, in one month. How would you express the rate of conversion of the zinc?
• How does the addition of a catalyst affect reaction rate?
• Question #9345d
• Why is most-probable speed correspond to the top of the Maxwell-Boltzmann distribution curve, even though the root-mean-square speed is the highest? Why are average and root-mean-square to the right?
• Question #e7fac
• If the activation energy of a reaction is zero, what does that mean for the reaction rate? What is now the only thing that it depends on that changes with temperature?
• How is the activation energy of a reaction like a wall or barrier?
• Question #8cf92
• For the reaction #2A(g) -> B(g) + C(s)#, find the rate constant at constant temperature and volume?
• Question #a6494
• What is the order of the reaction #A -> B# if changing the concentration of #A# from #"0.05 M"# to #"0.1 M"# changes the rate from #2 xx 10^(-3) "M/s"# to #1.6 xx 10^(-2) "M/s"#?
• Question #07e8f
• Why does a higher temperature cause a reaction to go faster?
• How is this pressure problem solved?
• The following reaction is observed in a lab experiment: #A + 2B -> C + D# In this experiment, it required 750 s for the concentration of #C# to change from 0.333 M to 0.750 M. What is the rate of the reaction?
• If we know the rate constant, can't we find the reaction rate just by looking at the coefficients?
• Question #e42d6
• Question #0cd0c
• Question #2896d
• Question #ab272
• What is a first order half life?
• Question #66e6d
• How does the presence of a catalyst affect the enthalpy change of a reaction?
• For the reaction #X + Y -> Z#, the following data was obtained. Answer the following questions? Is there any missing info I need to do this?? What is the best way to learn kinetics?
• During this reaction, #P_4 + 5O_2 -> P_4O_10#, 1.5 moles of product were made in 30 seconds. What is the rate of reaction?
• Does increased temperature generally decrease or increase the rate of a reaction?
• The following reaction was monitored as a function of time: #AB -> A + B#. A plot of #1/[AB]# versus time yields a straight line with slope #5.6xx10^(-2) (M.s)^-1#. What is the value of the rate constant (k) for this reaction temperature?
• What can be used to speed up a reaction?
• Part A The rate constant for a certain reaction is k = #7.00xx10^-3# #s^-1#. If the initial reactant concentration was 0.600 M, what will the concentration be after 19.0 minutes?
• If a temperature increase from 19.0 C to 33.0 C triples the rate constant for a reaction, what is the value of the activation barrier for the reaction?
• Why does a catalyst help a reaction proceed at a faster rate?
• In general, what is the relationship between temperature and the rate for a chemical reaction?
• What change will slow the rate of a chemical reaction?
• Hydrogen peroxide (#H_2O_2#) naturally breaks down into #H_2O# and #O_2# over time. When manganese dioxide (#MnO_2#) is added, the rate of this reaction increases. Based on this information, what can be hypothesized?
• In a reaction of combustion of #H_2#, when #H_2# concentration is kept constant, the amount of #H_2# reacting increases. Explain the order of the reaction with respect to #H_2# and #O_2#?
• What is a catalyst defined as?
• When a bottle of conc. ammonia is opened next to an open bottle of conc. hydrochloric acid, a fine white residue forms in mid-air BETWEEN the open bottles. How do we rationalize this observation?
• The rate constant of the reaction #O(g) + Na_2(g) -> NO(g) + N(g)#, occurring in the stratosphere, is #9.7 x 10^10 L mol^-1s^-1# at 800 C. The activation energy of the reaction is 315 kJ/mol. How do you determine the rate constant at 700 C?
• The rate constant of a reaction at 32°C is measured to be #"0.055 s"^(-1)#. If the frequency factor is #1.2xx10^13s^-1#, what is the activation barrier?
• Question #9b62e
• Question #d3beb
• Given the reaction #A -> B#, if the rate multiplies by #100# when the concentration of #A# is multiplied by #10#, what is the order of the reaction?
• Question #37a30
• What speeds up chemical reactions?
• Question #d6345
• What determines the rate of a reaction?
• What is the result of using a catalyst in a chemical reaction?
• What most likely happens to the rate of reaction of a human enzyme when the temperature is increased gradually from 10 degrees Celsius to 30 degrees Celsius?
• Question #1d00a
• What role does catalase play in this reaction?
• Question #84ebc
• Are enzymes specific for their reaction or can they react with any substrate? Why?
• In terms of kinetic theory, why does an increase in temperature increase the reaction rate?
• What can affect the activity of enzymes?
• Please help me! Is it possible that lactic acid can be reacted with concentrated aqueous solution of potassium alum at pH 3 ????? Please answer my question with explanation Thank you so much?
• HI→H2 + I2 which order reaction?
• What is a catalyst, and how are they used in the chemical industry?
• The rate constant for a reaction at 25.0 degrees C is 0.010 #s^-1# and its activation energy is 35.8 KJ. How do you find the rate constant at 50.0 degrees C?
• Do enzymes absorb excess heat so that reactions occur at low temperatures?
• Are enzymes used up in reactions?
• Do enzymes raise the activation energy of a reaction?
• Do enzymes lower the activation energy of a reaction?
• What is used to lower the energy required to make a reaction take place? It makes chemical reactions go faster without being consumed.?
• Why are enzymes considered to be catalyst of reaction?
• If the activation energy of a certain reaction is #"125 kJ/mol"#, and the reaction is at #"312.00 K"#, at what new temperature would its rate constant be twice as large?
• What does an enzyme decrease in order to increase the rate of a chemical reaction?
• Question #f0861
• How do you determine the speed of a reaction?
• What is carbonation? Please explain in details. Thank you :)
• A certain first-order reaction has a rate of #"0.04 M/s"# after 10 seconds and #"0.03 M/s"# after 20 seconds. What is the half-life for this reaction?
• What is the term for the reactants in an enzyme catalyzed reaction?
• The rate of the following reaction is 0.960 M/s. What is the relative rate of change of each species in the reaction? #A + 3B -> 2C#
• What do catalysts, like enzymes, do to chemical reactions?
• Is the half-life of a first-order decay dependent on temperature?
• How can adding heat to a reaction change the rate of a chemical reaction?
• Can you control the rate of a reaction by changing the activation energy needed?
• To increase the rate of a reaction, why would you increase the concentration of the reactants?
• Determine #f#, #c# and #p# in these reactions (Gibbs' Phase Rule)?
• #2A(g) + B(g) -> C(g)#. Rate = #k[A]^2[B]#. At the beginning of one trial of this reaction, [A] = 4.0 M and [B] = 1.0 M. The observed rate was 0.048 #"mol"*"L"^(-1)*"s"^(-1)#. What is the value of the rate constant for this reaction closest to?
• What is the rate constant for dimethyl ether after a couple of hours?
• Question #a8194
• What will occur if a catalyst is added to a reaction mixture?
• What kind of biological molecule speeds up chemical reactions and decreases activation energy?
• What speeds up chemical reactions involving proteins?
• How do you determine the rate of a reaction that follows the rate law: rate = #k[A]^m[B]^n#, where k = #1 x 10^-2#, [A] = 2 M, [B] = 3 M, m = 2, and n = 1?
• How is the half-life of a first-order reaction affected by change in concentration?
• How does an increase in surface area affect the rate of a chemical reaction?
• What is the half-life of a first-order reaction at #40^@ "C"# if its half-life at #25^@ "C"# was #"400 s"# and the activation energy is #"80 kJ/mol"#?
• Question #72a23
• A certain reaction has an activation energy of 70.0 kJ/mol and a frequency factor of #A = 1.40 xx 10^12 "M"^(-1)"s"^(-1)#. What is the rate constant, #k#, of this reaction at #22.0 °"C"#?
• Question #a644b
• Starting with #"1.20 g"# of #A#, what is the mass of #A# remaining undecomposed after #"1.00 h"#?
• How do you find the rate of reaction given the rate constant and concentrations if you don’t have the time?
• Why does the rate of reaction decrease over time?
• What purpose does the overall order of reaction serve? Once I've calculated it, what information can it provide me with?
• What is instantaneous rate of reaction? and how we can determine it?
• Question #613c4
• If the rate constant is #3.5 xx 10^(-3) "s"^(-1)# for a first order decay of reactant #A#, how long does it take the reaction to get to #24%# completion?
• Question #4ee02
• Question #c7286
• What is a catalyst?
• A chemist's rule of thumb is that #10^@ "C"# of difference results in a two-fold change in the reaction rate. If the temperature is varied from #35^@ "C"# to #45^@ "C"# for the rxn of crystal violet with hydroxide, by what factor does the rate multiply?
• Question #271ba
• Question #6072e
• Why is the change in concentration of a reactant negative?
• What is the formula for kinetic energy?
• What are digestive chemicals that speed up reactions called?
• Question #8d6ed
• Question #c6bfa
• What is the relationship between surface area and reaction rate?
• Question #45035
• Question #d01e3
• Are catalysts substances that speed up chemical reaction by the activation energy required?
• Catalysts are substances that speed up chemical reaction by doing what?
• What are catalysts?
• For the reaction #2A + B -> 3C#, if the rate of disappearance of #B# is #"0.30 mol/L"cdot"s"#, how do you set up a calculation to determine the rate of disappearance of #A# and appearance of #C#?
• The temperature coefficient for a certain reaction is #2#. If the temperature of the reaction was raised by #"40 K"#, what is the approximate factor to which the rate is multiplied?
• Question #7b731
• Explain why photochemical reactions are generally zero order?
• What is the order of the reaction of a single collison?
• Does increasing the temperature affect the rate of reaction?
• What is a substance that speeds up the rate of a chemical reaction without being used up itself or changed is called?
• The reaction time in a laboratory setting is how many seconds?
• Will increasing the surface are of the reactants increase or decrease the rate of a reaction?
• Will increasing the activation energy increase or decrease the rate of a reaction?
• Will adding an inhibitor increase or decrease the rate of a reaction?
• The rate of solvolysis of # CH_3COCl # is greater than # CH_3CH_2Cl#. why?
• Question #706ce
• Do reactions happen faster or slower in the summer or winter?
• Question #5e4ac
• Question #b758b
• Explain with a well-labelled diagram, the concept of activation energy, and how a catalyst affects such energy?
• If a gas begins at #"600 cm"^3# and its pressure increases by #"30 kPa"# from #"100 kPa"# of pressure in one minute, what is the average rate of change in volume per unit time?
• The reaction between marble chips and hydrochloride acid is given as: CaCO3+2HCl---> CaCl2+CO2+H2O (T=25C) What is effect on rate of reaction if: 1)Marble chips are replaced by grind marble 2) temperature is raised to 35C?
• How does the length of time it takes for a reaction to occur relate to the rate of the reaction?
• Which would not be affected by the addition of a catalyst?
• What happens to the particles in a substance when heat is added?
• What are 5 factors that affect reaction rates?
• A chemistry book lists the rate constant for a reaction as 34.5 #(1)/(M*s)#. What is the overall order of the reaction?
• Question #50ade
• What is the first-order half-life for #"0.50 M"# of a substance whose radioactive decay has a rate constant of #0.69 xx 10^(-2) "min"^(-1)#?
• How is the energy level of the products affected by the presence of a catalyst?
• Why does a catalyst cause a reaction to speed up?
• What is the explanation for why a higher temperature makes a reaction go faster?
• How is a catalyst is used in a reaction?
• Question #ae9bf
• Question #0b1c2
• If the units of a gas-phase rate constant are #"atm"^(-1)cdot"s"^(-1)#, then what is the order of the overall reaction?
• Question #cef19
• Question #4bc86
• A general rule of thumb is that a reaction #"10 K"# higher should be twice as fast. Predict how much faster a reaction is when the temperature is changed from #10^@"C"# to #100^@ "C"#?
• What happens as reactants get consumed while approaching a chemical equilibrium?
• At 20 °C, a 1.2 gram sample of Mg ribbon reacts rapidly with 10.0 milliliters of 1.0 M HCI(aq). Which change in conditions would have caused reaction to proceed more slowly?
• For a given chemical reaction, the addition of a catalyst provides a different reaction pathway that does what?
• What is the order for the reaction #2"N"_2"O"_5(g) -> 4"NO"_2(g) + "O"_2(g)#?
• Consider the reaction 3A + B + C ---> D + E where the rate law is defined as -D[A]/Dt=k[A]^2[B][C]?
• Given the following graph for a reactant concentration as a function of time, estimate the instantaneous rate of reaction at #"40 s"#?
• How do I determine the units of the rate constant for a zero order, first order, second order, and third order reaction?
• For a reaction whose mechanism is given below with initial rate #"0.0030 M/s"#, #(a)# what is the new rate if #["A"]# is doubled, #(b)# if #["B"]# is doubled, and #(c)# if both #["A"]# and #["B"]# are multiplied by #5#?
• Why does a more concentrated reactant means a faster reaction rate?
• Question #fae85
• Help with these kinetics questions about reaction order with respect to one reactant #A#??
• What are catalysts?
• Are catalysts allowed to remain in the product mixture after reaction is complete?
• How does addition of a catalyst affect the rate of [reaction]?
• For a reaction #A -> B#, why do we put a negative sign in front of the rate of disappearance of #A#?
• 1. A reaction has #Δ_text(r)H = "+100 kJ·mol"^"-1"#. Is the reaction exothermic or endothermic?
• Question #009ad
• Question #4421d
• Does a catalyst change the thermodynamics of a chemical reaction?
• Question #6a26e
• Question #c6aad
• Which of the following is the correct expression for the rate of the following reaction? Note: not all species are gaseous. CuO(s) + H2S (g) <--> Cu(s) + H2O (g)
• Question #1039c
• Rate of reactions problem?
• What do we call something that RETARDS the rate of reaction?
• What is the order of the reaction if doubling the concentration of #A# divides the half-life in 4?
• Motor vehicles equipped with catalytic converter should run on unleaded petrol .give reason?
• The half life of a first order reaction is one hour. During what time interval will the concentration be reduced to 7/8 of its initial value?
• The following two reactions are proposed as elementary steps in the mechanism for an overall reaction: (1) NO2Cl(g)---> NO2(g) + Cl(g) (2) NO2Cl(g) + Cl(g) ---> NO2(g) + Cl2(g) ?
• If the concentration of #NH_3# (from reaction below) is changing at a rate of #0.25# M/sec, what is the rate of change of #H_2# (in M/sec)?