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Chemical Kinetics

Solving for Activation Energy

Question: Activation Energy. Use the data below to answer the following questions about a chemical reaction. A. What is the activation energy for the chemical reaction? B. What is the value of the rate constant at 430.0 K? Temperature (Degrees°C) k (1/s) 189.7 2.52 x 10-5 198.9

Catalyst Decomposition Mechanism

Acetaldehyde can undergo catalytic decomposition according to the mechanism below: CH3CHO + I2 = CH3I + HI + CO (RDS) CH3I + HI = CH4 + I2 Use the mechanism to determine: a. the overall chemical equation b the catalyst c the intermediates d. the rate law

Gas Laws Problems

1. How do you find the ratio of rates (in grahams law) when you only are given the molar masses? 2. How do you find the t2 when you are given P1, t1, V1, and P2, and V2?

Kinetics, 1/2 life question

Can you please explain how we are using the half life equation in this question? to get mass in grams after 13 days. The question is as follows: Gallium-67 (t 1/2 = 78.25 hours) is used to diagnose certain tumors. If you ingest 0.055 mg of 67 GA what mass will remain in 13 days. I started out using the integrated rate

First Order Reaction

The following first order reaction is conducted in an inert liquid at 45 celsius: N2O5 N2O4 + 1/2 O2 THE RATE CONSTANT IS K=6.2*10 XY TO -4 SXY -1 AN 80.0g SAMPLE OF N2O5 IS DISSOLVED IN THE INERT LIQUID AND ALLOWED TO DECOMPOSE AT 45 CELSIUS. 1- HOW LONG WILL IT TAKE FOR THE QUANTITY OF N2O5 TO BE REDUCED TO 2.

Law of effusion and molar mass

Please explain the below problems, thanks: A polymer chemist dissolves 6.053g of poly(vinyl alcohol) in enough water to make 100.0mL of solution. At 25 C, the osmotic pressure of this solution [w/respect to pure water] is 0.272atm. What's the molar mass of the polymer sample? ans: 5.44x10^3 ------------------- A b

Specific Rate Constant

Evaluate the specific rate constant for the reaction at the temperature for which the data were obtained. The rate-law expression is rate=k[A][B]squared. A + B>>>>>> C Experiment Initial [A] Initial [B] Initial Rate of Formation of C 1 0.10 M 0.10 M

Apply steady-state approximation

Consider the following mechanism for the reaction of nitric oxide with hydrogen: 1) 2NO ----> N2O2 <---- 2) N2O2 + H2 -----> N2 + H2O2 3) H2O2 + H2 ----> 2 H2O a) apply the steady state approximation to one or more of the intermediates and thence derive the rate law for the overall reaction. B) unde

Reaction rate and tempersture

For the reaction: C2H4(g) + H2(g)----> C2H6(g) the activation energy is 181kJ/mol. The rate constant at 1000 degrees celsius is 1.6 x 10^3 L/mol/s. A.) at what temperature is the rate constant half its value at 1000 degrees Celsius? B.) What is the rate constant at 725 degrees Celsius?

Rate expression for Reaction

The equation for the reaction between iodide and bromate in acidic solution is 6I-(aq) + BrO3-(aq) + 6H+(aq) ---> 3I2(aq) + Br-(aq) + 3H2O The rate of the reaction is followed by measuring the appearance of I2. The following data are obtained. [I-] [BrO3-] [H+] Initial Rate (mo

Zero order reaction

For the zero order decomposistion of HI on a gold surface it takes 1.0 seconds for the concentration of HI to drop from 0.335M to 0.285M. HI(g)---> 1/2H2(g)+1/2I2 I need to know what is the rate constant for the reaction, how long will it take for the concentration of a 0.650M solution to drop to 0.0100M, and what is the hal

Beta decay

A 25.0 mg sample of 148/58 CE (t 1/2=48s) undergoes beta decay. After 4.50 min, how much of the original sample is left, what is the product formed and how much of the product is formed?

Oxidation Experiment

If you had the follwing two oxides: Hematite (Fe2O3), magnetite(Fe3O4) How would you conduct a simple experiment to show the different oxides of Iron? Thank you so much! PS. In my lab, we just did an experiment with AL and two different unknown Copper oxides: Cu2O and CuO. We were given one of the unknown copper oxid

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