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# Chemical Kinetics

### Rates of Reaction Problem

A particular reaction was found to depend on the concentration of the hydroxyl ion [OH-]. The initial rates varied as a function of initial pOH as follows: pOH 2.699 2.398 2.097 initial rate 1.600e-2 6.400e-2 2.560e-1 (M/s) Predict the initial reaction rate when pOH is 2.155.

### Reactions

For the reaction BrO3- + 5 Br- + 6 H+ ---> 3 Br2 + 3 H2O at a particular time, -/[BrO3-]// t = 1.5 10-2 M/s. What is -/[Br-]//t at the same instant? Question 2 Question: The reaction A + 2 B ---> products has been found to have the rate law, rate = k [A]

### Concentration of Nitric Oxide in Equilibrium with Nitrogen and Oxygen

At combustion temperatures, the equilibrium constant for the reaction N2 + O2 -> 2NO is about 5.0*10^-14. Calculate the concentration of nitric oxide that is in equilibrium with atmospheric levels of nitrogen and oxygen.

### Arrhenius Equation

The Arrhenius equation relates reaction rates to temperature via the activation energy. Calculate the ratio of the rates at -30 degrees C (a typical stratospheric temperature) for two biomolecular reactions having the same Arrhenius A factor and initial concentrations , one of which is endothermic and has an activation energy of

### How to reach 1st, 2nd, 3rd order and the rate law

Please explain how to reach 1st, 2nd, 3rd order and the rate law: What do they mean? How do I reach them? Differential, not integrated).

### Rate Mechanisms and Their Structure

Please show all work and keep things as simple as possible in the following three problems on chemistry and its rate mechanisms. The Rate Law. 1) A possible mechanism for the reaction between H2 and CO is shown below, where RDS is the rate-determining step. What is the rate law for the overall reaction? H2 ? 2 H

### Reactions, Concentration, Half-Life, and Activation Energies

Please explain each step and label what each variable in an equation stands for. This class is second half of first year general chem so please to not get too advanced. Thanks Average Rate of Reaction. The initial concentration of butyl chloride is 0.1000 M. What is the average rate of reaction if the chemical reaction be

### Chemical Kinetics

Chemists commonly use a rule of thumb that an increase of 10 K in temperature doubles the rate of a reaction. What must the activation energy be for this statement to be true for a temperature increase from 49 to 59°C?

### Chemical Kinetics - Integrated Law for Reaction

The reaction A produces B + C is known to be zero order in A and to have a rate constant of 5.0 x 10 superscript-2 mol/L x sec. @ 25 degrees C. An experiment was run at 25 degrees C where [A]0 = 1.0 x 10 superscript-3 M. a) Write the integrated law for this reaction b) Calculate the half-life for this reaction c) Calculate

### Rate Law and Value of Rate Constant

1) The reaction 2NO(g) + Cl2 produces 2NOCl(g) was studied at -10 degrees C. The following results were obtained Rate = Delta[Cl2] over Delta t. [NO]0 (mol/L) 0.10, 0.10, 1.20 [Cl2]0 (mol/L) 0.10, 0.20, 0.20 Initial Rate(mol/L*min) 0.18, 0.36, 1.45 a) What is rate law? b) What is the value of the rate constant?

### Activation energy and rate of reaction

The activation energy of a certain reaction is 76.7 kj/mol. How many times faster will the reaction occur at 62 degrees C than at 5 degrees C?

### Molecular speeds; effusion

If 4.83 ml of an unknown gas effuses through a hole in a plate in the same time it takes 9.23 ml of Argon to effuse through the same whole under the same conditions, what is the molecular weight of the unknown gas?

### Kinetic Molecules in Blood Binding Oxygen

Hemoglobin (Hb) molecules in blood bind oxygen and carry it to the cells, where it takes part in respiration. The first step in the binding of oxygen is first order in hemoglobin and first order in dissolved oxygen, with a rate constant of 4 x 10^7 L mol-1 S-1. Hb(aq) + O2(aq) ------------> (HbO2) (aq) How can I calcula

### Rate Processes Equations

The decomposition of benzene diazonium chloride (C6H5N2Cl, molar mass = 141 g/mol) at 50 degrees Celsius follows the first order kinetics rate law with the reaction equation: C6H5N2Cl-->C6H5Cl + N2, and has a half-life of 10.8 minutes. Exactly one liter of a solution of 10.0 g/L of benzene diazonium chloride is reacted and the g

### Determining the Rate Equation

Into a thoroughly washed and dried Erlenmeyer flask, place the required amount of H2C2O4 and any distilled water. The amounts are dictated by the experiment that you are doing. Reagents exp.1 exp. 2 exp.3 H2C2O4 20.00ml 20.00ml 10.00ml KMnO4 10.00ml 5.00ml 10.00ml H2O 0.00 ml

### Solving for Activation Energy from Variables

Data: T1 = 650 T2 = 700 K1 = 0.22 1/m.s K2 = 1.3 1/m.s Ea = R = 8.315 kj/K.mol I am using equation ln k2 - ln k1 = Ln k2/k1 = Ea /R [1/T2 - 1/T1] Since K1 + K2 are in 1/m.s do I have to get the inverse of those figures so that K1 = 4.545 m.s and K2 = .769 m.s? Second, solving for Ea: Ea/8.315 kj/k.mol * [1/7

### Gas Problem

Ammonia gas at 223 deg C and 90. atm flows into a reactor at a rate of 500. L/min. Carbon dioxide at 223 deg C and 47 atm flows into the reactor at a rate of 600. L/min. What mass of urea is produced per minute by this reaction assuming 100% yield?

### Animal Testing and Estimation Calculations

1. Animal rights groups often target the LD50 standard as an example of callous indifference to animal welfare. Other groups argue that standards such as LD50 are necessary to ensure drug safety and effectiveness. Take a position on the issue and write a letter to the editor of a newspaper defending your position. 2. During a

### Calculating the Rate of Reaction

CH3OH + HCl > CH3Cl + H2O The above is a chemical reaction. Below are data, time intervals and levels of concentration that it takes for HCl to react. Time (min) HCl (M) 0 1.85 79 1.67 158 1.52 316 1.30 632 1.00 How

### Enzyme Kinetics

The enzyme succinoxidase adds oxygen to succinate to give fumarate. The reaction follows Michaelis-Menton kinetics. The following rate data were determined for a solution in which the enzyme concentration is 10.0 uM: [S](mM) ----------------- 0.33 10.00 vo (uM s-1) at 20 C ----- 0.50 1.17

### Reaction Kinetics Equations

In aqueous solution, the reaction of A to form B has the following rate expression: -d[A]/dt = k[A]{1 + k'[H+]} From the pH dependence of the reaction, k' was found to be 1.0 x 10e5 M-1. In a pH 4.0 buffer, it took 5 min for a 0.30 M solution of A to react to give 0.15 M solution B. Calculate the value of k and g

### Working with Radio Active Decay

How many atoms decay in 24 hours in a 2.5 x 10(exponent negative 6) Ci source? 1 Ci=3.700 x 10(exponent 10) atom/s. Please show how you arrive at the solution. a. 0.22 atoms b. 1.3 x 10(exponent 21) atoms c. 9.3 x 10(exponent 4) atoms d. 2.3 x 10(exponent 6) atoms e. 8.0 x 10(exponent 9) atoms.

### Rate equation

For the second order reaction below, the concentration of A after 125 seconds is 0.0722M. If k=9.11x10(exponent negative 2) seconds(exponent negative 1), what ws the initial concentration of A? 2A-->B

### By what ratio will the rate constant change?

For a certain reaction, the activation energy is 52.1 kJ/mole. By what ratio will the rate constant change if the temperature is decreased from 175 degrees celsius to 75 degrees celsius? a. 0.00402 b. 0.0179 c. 0.996 d. 121 e. 249

### Multiple choice question on what affects the value of the rate constant.

Which of the following may affect the value of the rate constant? a. catalysts b. concentrations of reactants c. temperature d. answers b and c e. answers a, b, and c

### Determine the units of the rate constant.

What are the units of the rate constant for the following expression: rate=k[A](exponent 2)[B]

### Rate Equation from Continuous Stirred-Tank Reactor Data

Please see the attached file for the fully formatted problem(s). Problem: From the following data find a satisfactory rate equation for the gas-phase decomposition of pure A, A ---> R + S, in a mixed flow reactor. Tau based on Inlet feed conditions, sec 0.423 5.1 13.5 44.0 192 XA (for CAo = 0.002 mol/lit) 0.22 0.

### Kinetics of N2O: Finding the Reaction Rate from Percent Decomposition Data

Please see the attached file for the fully formatted problem(s). Establish the kinetics of the thermal decomposition of Nitrous oxide from the following data and find the reaction rate at 990 oC and an initial pressure of 200 mm Hg. t, min 20 53 100 % decomposition 23 50 73

### How do I predict, using the Michaelis-Menten equation

Aim: I am investigating the changes of hydrogen peroxide concentration on the rate of decomposition of catalase. Outline of method: The apparatus involve yeast(catalase), hydrogen peroxide, a 100cm3 gas syringe to collect oxygen. I am calculating the volume of gas collected in 30 seconds. The concentrations I plan to

### Using experimental results to determine the order of a chemical reaction and the rate constant from your understanding of chemical kinetics and species half life.

A reaction is defined by the following scheme: X à  Y When the concentration of X in a solution is 1.02 M, the half-life (t1/2) is 160 seconds. When the concentration of X in solution is 2.05 M, the half-life (t1/2) is 80 seconds. The above information applies when the reaction takes place at 25 degrees Celsius.