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Chemical Kinetics

Calculation of Settling Tank Size

6.10) A final settling tank for a 2-million-gallon-per-day (2mgd) activated-sludge treatment plant it to be designed to have an average overflow rate of 800 g/day-ft^2. the tank needs to have a minimum detention time of 2.0 hr and to allow proper settling it must be at least 11 ft deep. If the tank is circular, what should its d

Biochemical Oxygen Demand

Info: BOD: Biochemical Oxygen Demand BOD5 is the total amount of oxygen consumed by microorganisms during the first five days of biodegradation BOD5 = (DOi - Dof)/(P) this is the five-day BOD of a diluted sample Where DOi = the initial dissolved oxygen (DO) of the diluted wastewater DOf = the final DO of

Assistance with finding the ultimate carbonaceous BOD, reaction rate coefficient, and BOD5 at 15 degrees Centigrade given a BOD5 of 150 mg/L at 20 degrees Centigrade and reaction rate k at that temperature of 0.23/day.

Info: BOD: Biochemical Oxygen Demand BOD5 is the total amount of oxygen consumed by microorganisms during the first five days of biodegradation BOD5 = (DOi - Dof)/(P) this is the five-day BOD of a diluted sample Where DOi = the initial dissolved oxygen (DO) of the diluted wastewater DOf = the final DO of

Energy Consumption: Oil Consumption Rate

In 2000, the US accounted for one-fourth of the total world energy consumption and both the US and world rates were growing at a 3.5 percent annual rate. Suppose the US cut its growth rate to 1.1 percent, while the rest of the world growth propelled by the needs of developing countries, continued to increase by the historic rate

Reaction kinetics investigation

(See attached file for full problem description) The reaction between aquopentaaminecobaitfill) ions, {C0'(NH3)s{H20}i3+» and thiocyanate ions, NCS-, under certain conditions in aqueous solution at 7'0 "C has the following tilne-independent stoiohiometry {C0{3*|Ha)s{H20)}3+ "' N95' = {C°(NH3)5(NC5)}I* + H19 (1) The results

Rate Constant and Order of Reactions

I need help understanding how to determine orders of reaction: 1. For a first order reaction w/rate constant of .35 sec-1, the percent starting material remaining after 25 sec is: 2. Rate data for the reaction 2 NOBr (g)->; 2 NO (g) + Br2 (g) follows: [NOBr] Rate (mol L-1 s-1) .0450 1.62 x 10-3 .0310 7.69 x 10-4

Figures Relating to Cigarette Smoking and Cancer

Consider the following approximate figures relating to cigarette smoking and cancer. The death rate in the US population of 260 million is 12 deaths per 1000 persons per year. One-fifth of these deaths are from cancer and one-fourth of the cancer deaths are from lung cancer. Ninety percent of the lung cancer deaths occur among t

Activation Energy and Reaction Rates

The rearrangement of cyclopropane to propene has been studied at various temperatures. Experimental values for the rate constants are as follows (please see the attachment for the table). a) Determine the best value for the activation energy for this reaction b) Predict the best value for k at 500 K Make sure to acco

Reaction Rate, Temperature & the Arrhenius Equation

The rate of a particular reaction triples when the temprature is increased from 25C to 35C. Calculate the activation energy for this reaction. Also i just need to clearify the concept of Arrhenius Equation. What happened to Rate Constant(k) and the rate of reaction if: a. there is a decrease in temperature b. an increase in

Second order rate law calculations

Second order rate law: 1/[N02]=0.775L/(mol*s)* 645s+1/.0030mol/L= 8.3*10^2L/mol Please provide step-by-step mathematical operation of the above.

Electrochemistry

2 The following table gives some results from experiments in which the current efficiency of zinc deposition in an electrowinning operation was determined at various current densities (amperes per square meter of cathode surface area). The cathode area at the plant is 10,000 m2. Current Density C

One of the most important products that we have in our daily diet is sugar.

One of the most important products that we have in our daily diet is sugar. The main type of sugar that we use is sucrose, which is a disaccharide consisting of glucose and fructose. The hydrolysis of sucrose to produce glucose and fructose occurs by the following overall reaction: C12H22O11(s) + H2O(l) yields C6H12O6(aq) + C

Determine the rate law for this reaction

For the reaction 3 A(g) + 2 B(g) yields 2 C(g) + 2 D(g) The following data were collected at constant temperature. Determine the rate law for this reaction and the value of the rate constant. Trial Initial [A] mol/L Initial [B] mol/L Initail rate mol/L min 1 0.200 0.100

Rate of reactions

1. The numerical value of the rate constant for the gaseous reaction 2N2O5 reacts to form 4No2 + O2 was found to be 5.80 times 10 exp -4. The initial concentration of N2O5 was 1.00 mol/L. Assuming all measurements are recorded in seconds, determine the time required for the reaction to be 60% complete. 2. Re

A grain sample was found in a cave.

A grain sample was found in a cave. The amount of carbon-14 in the sample was 1/16 the amount found in a fresh sample of grain. How old was the grain in the cave? The half-life of carbon-14 is 5600 years.

Reaction rate constant and kinetics

The reaction CH3CH2N02 + 0H^- -----> CH3CHN02^- + H20 has the rate r=k[CH3CH2N02][0H^-] it takes 0.5 min for one % of CH3CH2N02 to react at 25 degrees C, in the case of a solution 0.002 M in CH3CH2N02 and 0.3 M in Na0H. a) Calculate k. b) Calculate also how long it would take f

Benzyl Chloride with Solvent and Rate Limiting Step

With the starting reagents of benzyl chloride and a solvent (water), what is the rate limiting step in the solvolysis reactions: a. Solubility of the alkyl halide b. Formation of the carbocation c. Reaction of the carbocation with water d. Removal of a proton from alkyloxonium ion

Rates of Effusion

Which species, ^235(UF6) or ^238(UF6), would you expect to effuse faster through a porous membrane? How much faster, i.e. what are the relative rates of effusion?

Ratio of rates from Arrhenius equation

. Question : Two reactions have the same Arhenius frequency factor, while their energies of activation differ by 5020 Jmol-1. Calculate the ratio of their rate constants at 27degree Celsius

Rate Constant for Temperatures

As you are aware, temperature affects the rate of reactions. You have the following reaction: 2A + B = C (equilibrium is = sign). For this reaction at 25 degrees Celsius, the forward rate constant, kf, is larger than the reverse rate constant, kf (i.e., kf = 10 to the 3rd x kr). Would there be a temperature at which this re

Half-life and Periodic Trends

Because the time it takes for a reaction to actually reach equilibrium is infinite, scientists have used the estimate that after ten half-lives (or ten half-times) the reaction is completed (i.e., the reaction has reached equilibrium). Chlorine gas and solid sodium metal react to produce sodium chloride. If you place one mole

General Chemistry

Kc for the reaction below at 25°C is 4.8 x 10-6. Calculate the equilibrium concentration (mol/L) of Cl2(g) if the initial concentration of ICl(g) is 1.33 mol/L. There is no I2 or Cl2 initially present. 2ICl(g) <-> I2(g) + Cl2(g) a. 6.4 x 10-6

General Chemistry problems

1. The relationship between the rate constants for the forward and reverse reactions and the equilibrium constant for a process is K = ____________. a. kf/kr b. kfkr c. kf+kr d. kf-kr e. 1/(kfkr) 2. Consider the following equilibrium. 2 SO2(g) + O2(g) 2 SO3(g) From which of the following starting conditions would

Half-Life of Decay Process

A sample of radioactive curium was found to decay in a manner that follows a first order create reaction. After 1.00 year the activity of the sample had declined from 3012 disintegration per second (create as a concentration) to 2921 disintegration per second (treat as a concentration). What is the half-life of the decay process

Kinetics: various calculations

1) Calculate the mole fraction of methanol (CH OH) in a mixture of equal masses of methanol and water. 2) Calculate the molar concentration of chloride ions in a solution prepared by dissolving 454g of CaCl in water and diluting to 500mL. 3) At 25 degrees Celcius calcium chloride has a solubi

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

The Concentration-Time Equation

The first-order rate constant for the decomposition of an insecticide in water at degC is 1.45 1/yr. A quantity of this insecticide is washed into a lake on June 1, leading to a concentration of 5.0 x 10-7 g/cm3 of water. Assume that the effective temperature of the lake is degC. a. What is the concentration of the insect

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?