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Chemical Kinetics

Steady State Pollution Concentration from Box Model for City

1) Consider an urban area (100 km^2) with a temperature profile that decreases linearly with height between 30 degrees C at the surface, and 24 degrees C at 500 m. At 500 m, the temperature increases with height to 30 degrees C at 1000 m. What is the mixing height for this situation? Using a box model for the city, calculate

Five physical chemistry questions.

5) Ozone decomposes to oxygen according to the balance chemical equation below: 2O3 ---> 3O2 If the rate of disappearance of the ozone is -7.2E-4 M/s, what is the rate of formation of oxygen? 6) If 100kJ of heat is added to 54.0 g of water at 100°C, what is the final state of the water? MW H2O = 17.9 g/mole 7) How many

Vmax, Km: Calculation of Kinetic Constants, first order

The initial velocity of an enzyme catalyzed reaction was measured at a serious of different initial substrate concentrations in the table. Find Km (sometimes called Ks)(the half velocity constant) and ...there is moreshow problemThe initial velocity of an enzyme catalyzed reaction was measured at a serious of different initial s

Reaction data for the reaction of Pt(bipy)Cl2 with ethylenediamine was analyzed to obtain a rate constant and reaction orders. Graphs were produced and calculations performed.

In SXR205 Activity B, the kinetics of the reaction between the square-planar platinum complex dichloro-(2,2'-bipyridine) platinum (II) (Pt(bipy)Cl2) and 1,2-diaminoethane (en) were investigated. In a different study of this reaction, the data in Table 1 were obtained manually using a spectrometer set at a fixed wavelength of 274

Chemical Formulas for the ionic compounds

See attached file for full problem description. 1. what is the chemical formula for the following ternary compounds given their constituent ions a. lead(IV) sulfate b. stannous chlorite c. cobalt(II) hydroxide d. mercurous phosphate 2. Provide the formula for each of the following binary ionic compounds a. curprous su

Reaction Order

If the overall reaction is the sum of the order of the reagents, and: Zero order = changing concentration of the reactant does not affect the reaction rate. First order = doubling the concentration of any reactant doubles the reaction rate Second order = doubling the concentration of any reactant quadruples the reaction

Fractional Distillation

Explain why packed and spinning band fractional distillation columns are more efficient at separating two liquids having close boiling points than are unpacked columns.

Rates of Reactions - Simple

1. Explain why the rate of a simple chemical reaction such as: NO(g) + 1O2(g) → NO2(g) is likely to be most rapid at the beginning of the reaction. 2. If you wish to dissolve a lump of sugar in water, give three ways you could increase the rate at which the sugar dissolves? Explain why each procedure is effective.

Methanol Production Process

Methanol production process is operated at temperatures of 25 - 30 degrees & a pressure of 50 - 100 atmospheres, in the presence of a copper based catalyst. Comment on whether these operating conditions (250 - 300 degrees & 50-100 atmospheres) are consistent with the aims of achieving a high equilibrium yield of methanol and a h


1.) At 40 degrees Celsius CH2O2(aq) will decompose according to the following reaction: 2H2O2(aq) ----- 2H2O(l) + O2(g) The following data were collected for the concentration of H2O2 at various times. Times(s) [H2

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

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.


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

Rate Constant

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

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 Arhenius 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

General Chemistry

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