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Chemical Kinetics

Determining Partial and Total Pressure: Dimethyl Ether Example

The decomposition of dimethyl ether at 504 degrees Celsius is a first-order reaction with a half-life of 27.0 min. (CH3)2O (g) ----> CH4 (g) + H2 (g) + CO (g) (a) What will be the partial pressure of (CH3)2O (g) after 1.29 h if its initial partial pressure was 596 mmHg? (in mmHg) (b) What will be the total ga

Reaction Rates

The rate of the following reaction in aqueous solution is monitored by measuring the rate of formation of (I3^-). The data obtained is listed in the table. (S2O8^2-) + (3I^-) ----> (2SO4^2-) + (I3^-) Experiment ([S2O8]^2-), M ([I]^-),M Initial rate, M s^1- 1 0

Reaction Rates

In the reaction A + 2B ----> C + 3D, the rate of disappearance of B is -7.6 x 10^-4 mol L^-1 s^-1. (a) What is the rate of disappearance of A? (in mol/L^-1 s^-1) (b) What is the rate of formation of D? (in mol/L^-1 s^-1) (c) What is the "rate of the reaction"? (in mol/L^-1 s^-1)

decomposition of H2O2

In the reaction 2H2O2 (aq) ------> 2H2O (l) + O2 (g), the initial concentration of H2O2 is 0.2504 mol/L, the initial rate of decomposition of H2O2 is 9.32 x 10^-4 mol L^-1s^-1. What will be [H2O2] at t= 36s?

Steady State Radon Concentration in the Basement of a House

Radioactive radon gas (222Rn) enters an average building at a rate of 4 picocuries per second per square meter of foundation area. Consider a house with a foundation of 200 square meters and a volume of 1000 cubic meters. Assume the house if well designed for energy conservation so that the ventilation rate is low and only one t

Solubility of Alum Amongst Paper By-Products

Problem Statement: Chemical XYZ is added to a substrate at a defined rate of 1.17% of the dry weight of the substrate; paper makers alum (Al2(SO4)3-14H2O) is added to the substrate at a rate of 45% of the Chemical XYZ rate; the dry weight of the substrate is given as 1460 lbs/1000 ft2 The molecular weight of the alum is g

Rate Equation for Atmospheric Oxidation of S(IV) to S(VI)

A) Calculate the liquid phase / gas phase ratio for SO2, HNO3, HCl and H2O2 in a cloud droplet (L= 10-6) and determine which phase dominates. b) Explain why the atmospheric rate of formation of S(VI) in the aqueous phase is given by (Please see attachment for atmospheric rate of formation) where k is the liquid-phase rate

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

Calculating Reaction Order with an Excess of One Reactant

A+B -> C+D The complete data is as follows: The initial concentration of A is 400 mmol/L and initial concentration of B is 0.4 mmol/L. The following data is for concentration of C in mmol/L at different times T in seconds T sec: 0 120 240 360 Infinity [C] : 0 0.2 0.3 0.35 0.4 Assuming

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

Reaction Rates: Example Problem

A(g) + 5/8 B(g) --> C(g) + 3/4 D(g) If C is increasing at a rate of 4.0 mol/L*s, at what rate is B changing? Can you just multiply the rate change of 4.0 mol/L*s by 5/8ths to get the reaction rate. If so I got -2.5 mol/L*s.

Weak Electrolyte Undergoes Ionization

Water is a very weak electrolyte that undergoes the ionization- H2O= H+(aq) + OH-(aq) If k1= 2.4x 10-5 s-1 and k-1 = 1.3 x 10 to the eleventh/M*s What is the equilibrium constant K where K= [H=] [OH-]/[H2O] ? What is the product [H+][OH-] ? What is [H+] ? What is [OH-] ?

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


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.

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

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