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Chemical Kinetics

Rate Constant for a Second Order Reaction

The rate constant for the second-order reaction is 0.80/M*s at 10 degrees C 2NOBr(g) goes to 2NO(g) + Br2 (g). (a) Starting with a concentration of 0.071 M, calculate the concentration of NOBr after 25 seconds. (b) Calculate the half-life when [NOBr]0 =0.081M. (c) Find the half-life when [

Explanation of Arrhenius Law and Kinetics

I need help understanding the meaning and units involved in the Arrhenius Law equation. Assuming a first order reaction: k = Ae^-Ea/RT 1) Can this be re-written as: logk = -Ea/RT + constant ? What is the constant? 2) In either case: a) How do I determine or choose the activation energy Ea? Where would I find

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

EFFUSION

In an effusion experiment measuring distance as a function of time, an unknown gas moved 3.42 m in 60 s while O2 under identical conditions moved 4.84 m. Calculate the molar mass of the unknown gas? A. 16 B. 48 C.64 D. 45 E. 128

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.

Moles and Volume

A solution of an unknown agent was titrated with 30.0 mL of a 0.100 M chromate solution, which causes the chromate to be reduced to Cr3. If instead of chromate, a 0.100 M permanganate solution had been used that resulted in the formation of Mn2+, what volume of permanganate solution would be required?

I AM TRYING TO FIND THE ACTIVATION ENERGY

I AM TRYING TO FIND THE ACTIVATION ENERGY My slope is (-4295.5) My R is the Gas constant=8.314 How do I utilize the Arrhenius formula to get the Activation energy? Also, how do I calculate th slope of log K compared to 1/Temp?

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

Kinetics

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

Copper percipitate

Trying to figure out how much copper should precipitate from a reaction between .55g of zinc and 92.4mL of copper sulfate. What formula would I use?

Calculation using Gaussian plume model equation

29) A 200-MW power plant has a 100-m stack with raidus 2.5 m, flue gas exit velocity 13.5 m/s, and gas exit temperature 145 degrees Celsius. Ambient temperature is 15 degrees Celsius, windspeed at the stack is 5 m/s, and the atmosphere is stable, Class E, with a lapse rate of 5 C/km. if it emits 300 g/s of SO2, estimate the conc

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.