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Chemical Kinetics

Recognizing the Order of a Reaction

In the reaction 2 A + 2 B ----> C + 3 D the rate of disappearance of A is -2.2 X 10^-4 M s -1. What is the rate of formation of C? The answer states A = to 1.1 x 10^-4 M/s. What happened to the "-1" in this situation? Can these measures for rates, Ms^-1 and s-1, be used to help identify first second and third order?

Chemical Kinetics Problems

Please explain what the s-1 means in the rate constant calculation. Can you please describe in detail why this is being added on as a unit and what it is used for.

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.


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]

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

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?

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?

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?


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

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 Ea and A

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 Ho

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

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

Rate Constant Problem

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

Units of rate constant

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