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Chemical Kinetics

Chemical kinetics is the study of the rates of chemical reactions. It closely examines reaction rates by looking at external variables, such as experimental conditions, and internal variables, such as the formation of intermediates. Although chemical kinetics can be highly theoretical, it also deals with experimental determination of reaction rates through the application of rate laws, and experimentally-derived rate constants. In chemical kinetics, knowing which rate law to apply is heavily dependent on the order of the reaction. This describes the exponent to which the reactant’s concentration in the rate equation is raised to. Consider the following rate equation: r = k[A]^1 [B]^2 where r is the rate of reaction k is the rate constant [A] is the concentration of reactant A [B] is the concentration of reactant B So looking at the above rate equation, we can see that the order of reaction of A is 1, while the order of reaction of B is 2. However, the overall order of reaction is 3, through summing the reaction orders of both reactants. Using the above equation, doubling the concentration of the reactant A, while keeping the concentration of B constant, will double the rate of reaction. Doubling the concentration of B, while keeping the concentration of A constant, will quadruple the rate of reaction. However, doubling the concentration of both A and B, will increase the original reaction rate by eightfold. Thus, understanding Chemical Kinetics is crucial to understanding the rates of chemical processes, and the variables which affect them.

Kinetics in Chemical Reactor

See the attached file. 1. The reversible exothermic water-gas shift reaction (seen in attached file), takes place in an isobaric and adiabatic PFR reactor of V=1m3. Ftot = 100 moles/sec contains 40 mol% H20 and 20 mole % of inert I. The total pressure is 3 bar and the inlet temperature is Tin = 500 k. In parallel the methanatio

Calculating Residence Time of Atmospheric SO2

Natural sources add sulfur dioxide (SO2) to the atmosphere at a rate of about
1E8 tonnes (S)/yr. The background concentration of atmospheric SO2, measured
in remote areas where anthropogenic sources are not likely to have much influence,
is about 0.4 parts per billion, by volume. What is the residence time of

Zinc-containing enzyme carbonic anhydrase

(a) The zinc-containing enzyme carbonic anhydrase is present in the red blood cells of humans and catalyses the following physiologically important reaction. Please see the attached document for the reaction. Where the carbon dioxide produced during respiration is converted to hydrogen carbonate, which is very soluble in

Rate Law for Mechanism

Please show all work and explain the answer. Question For the reaction A+2B ---> E A. Give the rate law if the mechanism is: 2A+B ---->C (slow) B+C -----> D+A (fast) D--------->E (fast) B. Give the rate law if the mechanism is: 2A+B ------>C (fast) B+C -------> D+A (slow) D----------->E (fast)

Rate Law and Rate Constant

Question 1. Write the rate law and give the rate constant for this reaction. 2 ClO2(aq) + 2 OH^-(aq) ---> ClO-3(aq) + ClO2^-(aq) + H2O(l) The following rate data were collected: Experiment----------[ClO2]---------[OH-]-----------initial rate 1----------------------0.060M-------0.030M--------0.0248 M/s 2------------

Kinetics: Rate Law

i am clarifying this is not an assignemt is just practice questions. It was part of an old test that the teacher gave to us to practice . This are practice questions 1. Calculate deltaH for the reaction P4O10 + 6 PCl3 ----? 10 Cl3PO From P4 + 6 Cl2 -----> 4 PCl3 deltaH = -1225.6 kJ P4 + 5 O2 -----> P4O10 deltaH =

Rate of reaction: Example question

For the reaction o(g) + o3(g) --> 2O2(G) the preexponential factor is 4.8 x 10^9 mol s-l . Given the activation energy is 17.1 kJ mol, what is the rate of reaction at 298 k? What is the value of kb for the cyanide anion cn- given that ka= 4x10-4? Report to one significant figure.

Factor of a Reaction Rate

For the reaction O(g) + o3(g)--- > 2o2(g) the activation energy is 17.1 kJ/mol. By what factor does the reaction rate increase ongoing from 100k to 200? Consider the reaction A+2B --> 2C. If C is increasing at a rate of 7.0 mol L-1 s-1, at what rate is (A) changing?

Concentration, Saturation and Vapor Loss of a Gas in Tank

Hello: We are to assume a 129 m3 closed tank. The tank previously contained heptane and therefore has residual vapor. The vapor pressure is given and known as 40 mm Hg The temperature is given as 25 degrees C. 1) Is there a way to determine what the residual concentration of heptane gas would be in this closed con

Box model

Consider modeling the air over an area to be abox, 100km on each side that reaches an altitude of 1km. Clean mountain air blows into this box from the west with an average speed of 4m/s. A key pollutant is generated in this box at a rate of 10kg/s. The pollutant degrades in proportion to its concentration (k=.2(1/hr)) Find the

Kinetic Energy Problem

HWU3-2 QUESTION: A 1577 kg car is traveling down the road at 81.0 km/h. While traveling at this rate of speed, what is the kinetic energy of this vehicle in kilojoules? Answer: __________ kJ ________________________________________ HINT: Kinetic energy can be found using the formula E_k= 1/2 mv^2 where Ek is kinetic e

Rate of Reaction in Terms of Products and Reactants

1. Express the rate of reaction in terms of products and reactants 2. In the first 15 secs of the reaction, 0.015 mol of O2 is produced in a vessel with 0.500 L volume. What is the average reaction rate for this time interval? 3. Predict the change in N2O over the time interval.

Firefighter Health

Why are active on-duty firefighters likely to experience the adverse health effects from inhaling 300 ppm of carbon monoxide faster than nonactive off-duty firefighters who inhale the same concentration of the same substance? Explain your answer using the chemicals/process involved.

Lindemann mechanism

In the discussion of the Lindemann mechanism, it was assumed that the rate of activation by collisions with another reactant molecule, A, was the same with a non-reactant molecule, M, such as an inert gas. What if the rates of activation for these two process are different? In this case, the mechanism become k1

Rate law

Using this data calculate the rate law for the reaction A + B -> C [A] (M) [B] (M) Initial rate (M/s) 0.10 0.10 0.0092 0.20 0.20 0.0184 0.20 0.40 0.0368

Review Questions on Kinetics

Please can you provide an explanation for the following questions: For the rate law, Rate = k[A]2[B], which of the following is false about the chemical reaction having this rate law? A) Doubling [A] quadruples the rate. B) The reaction is third order overall. C) The chemical reaction must be: 2 A + B â?' C. D) Do

How to read a rate law and decide changes in the rate

In aqueous solution, iodine reacts with acetone as represented by the following stoichiometric equation: I2 + CH3COCH3---> CH3COCH2I + H+ + Iâ?" The experimental rate law is Rate = k[H+][CH3COCH3] According to the information above, an increase in the hydrogen ion concentration has what effect on the reaction? A) It d

Finding Rate of Reaction

An enzyme is a large protein molecule (typically with a molar mass greater than 20,000 AMU) that has a structure capable of catalyzing specific biological reactions. In general one or more reactant molecules (called substrates) bind to an enzyme at its "active sites" where the reaction the enzyme is responsible for occurs. The g

General Chemistry II: The Rate of a Reaction

Provide help with the following problem with the steps: Consider the reaction 2NO(g) + O2(g) --> 2NO2(g) Suppose that at a particular moment during the reaction nitric oxide (NO) is reacting at the rate of 0.066 M/s. (a). At what rate is NO2 being formed? (b) At what rate is molecular oxygen reacting?

At an altitude of about 35 kilometers

At an altitude of about 35 kilometers, the average concentrations of O* and of CH4 are approximately 100 and 1E11 molecules cm-3 respectively, and the rate constant k for the above reaction is approximately 2.9E-10 cm3 Molecules-1 s-1. Calculate the rate of destruction of methane in molecules per second per cubic centimeter.

Water Equilibrium

I missed this question on my exam. Can you show me the correct way to do it? H2O(l)= H+(aq) +OH(aq) If K1(reaction going towards right)= 2.4e-5/second and if K-1(reaction going towards left) = 1.3e11/M.s what is the equilibrium constant K where K= [H][OH]/[H2O]? what are the product values in Moles for [H][OH],

rate of reaction kinetics

Consider the following reaction: A+B----AB For a certain set of initial concentrations of A and B, it takes 10 seconds to produce 0.1 mmol of AB at 20 degrees celsius and 150 seconds at 0 degrees celsius. What is the ratio of the rate at 20 degrees to that at 0 degrees?

Solving Rate Constant Problems

A compound X undergoes two simultaneous first-order reactions as follows: X Y with rate constant k1 and X Z with rate constant k2. The ratio of k1/k2 at 40°C is 9.9. What is the ratio at 280°C? Assume that the frequency factors of the two reactions are the same. I used the equation ln k1/k2=(Ea/R)(T1-T2/T1*T2) my ans

Important information about Calculate Activation Energy

The rate constants of some reactions double with every 10 degree rise in temperature. Assume that a reaction takes place at 291 K and 301 K. What must the activation energy be for the rate constant to double as described? kJ/mol I have no idea where to start on this problem. I can't seem to figure out how to set up the ra

Calculate Activation Energy

The second-order rate constant for the decomposition of nitrous oxide (N2O) into a nitrogen molecule and oxygen atom has been measured at different temperatures given below. k(1/M·s) t(°C) 1.87 10-3 600 0.0113 650 0.0569 700 0.244 750 Determine graphically the activation energy for the reaction. I took 1/873 wa

Rate Constant for a Reaction

For the reaction given below, the frequency factor A is 8.7 1012 s-1 and the activation energy is 63 kJ/mol. NO(g) + O3(g) NO2(g) + O2(g) What is the rate constant for the reaction at 50°C? I used the equation k=Ae^(-Ea/RT) by plugging in the variables I got 8.5e12. But they say this is significantly off. where did i go