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Physical Chemistry

Pressure and Temperature Determination

Suggest the pressure and temperature at which 1.0 mol of (a) Nh3, (b) Xe, (c) He will be in states that correspond to 1.0 mol of H2 at 1.0 atm and 25 degrees Celsius. NH3: T = 3.64 x 10^3 K, p= 8.7 atm, Xe: T=2.60K, p=4.5 atm, He: T=46.7K, p=0.18 atm.

equation of gas state leading to critical behavior

Please see attached file. A scientist proposted the following equation of state P = RT/Vm -B/Vm^2 + C/Vm^3 where B and C are independent of the temperatures. Show that the equation leads to critical behavior. Find the critical constants of the gas in terms of B and C and expression for the critical compression factor

Equilibrium Expression of a Buffer

If you add Na2CO3 with NaHCO3 and distilled water what is the equilibrium expression for the buffer? And what is the weak buffer and the conjugate base? What Ions are present in the solution?

Initial Rate of Acetylaldehyde

1. The initial rate of acetylaldehyde, CH3CHO at 600ºC is CH↓3CHO(g) → CH↓4(g) + CO(g) Was measured at a series of concentrations with the following results: [CH3CHO] 0.10M 0.20M 0.30M 0.40M Rate(mol/L?s) 0.085 0.34 0.76 1.4 Using these data, determine the reaction order; that is, determine the valu

Equilibrium Shift of a Reaction and the pH of a Solution

1. The pressure on each of the following systems is decreased from 5 atm to 1 atm. Which way does the equilibrium shift in each of the following systems? a.) 2CO2 (g) --> 2CO (g) + O2 (g) b.) H2 (g) + I2 --> 2HI (g) 2. What is the pH of a solution if the H+ concentration is 7.2 X 10^-14 M? Is this neutral, acidic, or ba

PH and molarity of pure water

You add 5 drops of .100 M HCl to 100ml of "pure" water. Assuming that the volume of one drop is .035ml, calculate the expected pH of the resulting solution. .

Molar Concentrations

Calculate the molar concentrations, I-, disulfur octaoxide, disulfur trioxide. From [stock concentrations] 15 ml of .20 M potassium iodine, 20 ml of .10M K2S2O8, and 10 ml of .0050M Na2S2O3, I am supposed to figure out the molar concentrations of I-, disulfur octaoxide, and disulfur trioxide. First I thought just use the c

How many kilojoules of energy are liberated

In photosynthesis, the following reaction takes place: 6CO2 (g) + 6H2O (l) 6O2 (g) + C6H12O6 (s) H = -637 kJ. How many kilojoules of energy are liberated when 15.00 g of glucose, C6H12O6, is burned? (Round your answer to two decimal places)

heat realsed by combustion of ethyl ether

1. In earlier times, ethyl ether was commonly used as an anesthetic. It is, however, highly flammable. When 5.0 mL of ethyl ether C4H10 (l), (d=0.714 g/mL) is burned in a bomb calorimeter, the temperature rises from 23.5°C to 39.7. The calorimeter heat capacity is 10.24 kJ/°C. What is heat released when 5.00 mL ethyl ether is

Calculating Mass and Moles

GIVEN INFO: from an unknown bottle: Unknown= #25 Metal present= Na Mass% metal= 43.88% Atomic masses: Cl= 35.453g O= 16.0g C= 12.0g H= 1.00g 1. Mass of crucible and cover= 32.493g 2. Mass of crucible, cover, and unknown=33.001g 3. Mass of crucible, cover, and solid chloride= 33.017g -----------------------------

Chemical Reactions: Physical Chemistry

1. Some sulfuric acid is spilled on a lab bench. It can be neutralized by sprinkling sodium bicarbonate on it and then mopping up the resultant solution. The sodium bicarbonate reacts with sulfuric acid as follows. 2 NaHCO3(s) + H2SO4(aq) Na2SO4(aq) + 2 H2O(l) + 2 CO2(g) Sodium bicarbonate is added until the fizzing due to th

Chromate-dichromate equilibrium.

See attached file for full problem description. 1. How does the (H+) of the solution affect the CrO42-/Cr2O72- eqiuilibrium? 2. What poof was shown that CrO42- ions exist in a solution of K2Cr2O7. 3. In what way does OH- affect the equilibrium? Give two methods by which this ion upsets the equilibrium? 4. Write the e

Thermochemistry

Calculate the heat combustion for the following reaction from the standard enthalpies of formation? C2H4(g) + 3O2(g) yields 2CO2(g) + 2H2O(l)

Thermochemistry

Glauber's salt, sodium sulfate decahydrate (Na2SO4 * 10H2O) undergoes a phase transition (that is melting or freezing) at a convenient temp of 32 degrees C Na2SO4 * 1o H2O(s) yields Na2SO4 * 10 H2O(l) Change H = 74.4 kJ/mol As a result this compound is used to regulate the temperature in homes. It is placed in pl

Thermochemistry

Consider the reaction: H2(g) + Cl2(g) yields 2HCl(g) Change Heat = -184.6 If 6.00 moles of H2 react with 6.00 moles of Cl2 to form HCL, what is the change in kJ for this reaction at 1.0 atm and 25 degrees C. Assume the reaction goes to completion.

Energy in chemical reactions

See the attached document and find the heat of reaction for each set of reactions. Reaction 1: Heat of Dissolution of NaOH Reaction 2: Heat of Reaction Between Aqueous NaOH and Aqueous HCl Reaction 3: Heat of Reaction Between Solid NaOH and Aqueous HCl Questions: 1. Write the net ionic equation for each reaction,

Molarity of Bromophenol Blue Stock

You have 20 ml of 10% Bromophenol Blue (BPB). Using a 10% stock, how would you prepare 5 ml of a 0.2 % stock? (MW BPB is 670) Assume 1 % = 1 g/100ml. In addition, what is the molarity of the 0.2% BPB Stock?

pH and Temperature

The dissociation of water increases as the temperature is raised: H20 --> H+ + OH-. If you adjust a buffer to pH 7.4 at room temperature (25 degree Celsius), then cool it down to 4 degree Celsius for an enzyme assay, will the pH increase or decrease?

Buffer HEPES and MES got mixed. Identify which beaker contains HEPES.

You and a lab parnter prepare buffers to use in an experiment. Your partner prepares 200 ml 50 mM MES pH 6.0 while you prepare 200 ml of 50 mM HEPES pH 6.0. (MES and HEPES are the abbreviated names for two biological buffers often used in research labs). HEPES has MW 238.3 and pK = 7.48 MES has MW 195 and pK = 6.1 1. How

Calculating Delta S for reaction

1. At two different temperatures, the reaction A & B is allowed to reach equilibrium and Delta H is measure. Delta H =10.9 kJ/mol for this reaction at 5.5 C and Delta H=31.0 kJ/mol at 80.1 C. Calculate Delta S for this reaction at each of these two temperatures. (Hint Delta G = 0 at equilibrium).

Predicting Reactions and Calculating Quantity

Predict whether the following reaction would proceed spontaneously as written at 298 K by calculating both Delta G and e for the reaction, given that [Co2+] =.15 M and [Fe2+]= 0.68 M. ( E1/2= -0.282 for Co2+ + 2e- -----> Co0) Co0 + Fe2+ ---> Co2+ + Fe0 A current of 0.452 A is passed through an electrolytic cell co

Chemistry Help

1. How many grams of CO2 would be formed from 20 grams of C8H10 in the following (UNBALANCED) reaction? C8H10 + O2 --> CO2 + H2O 2. How many moles of CO2 would be formed from 40 grams of CaCO3 in the following (UNBALANCED) equation? CaCO3 + HCl --> CaCl2 + CO2 + H2O 3. A gas sample has an original volume of 700 ml when

Isopentane Questions

(a) The molar volume of isopentane (C5H12) is 1.00 L at 503 K and 30.0 atm. (i) Does isopentane behave like an ideal gas? Justify your answer. (ii) Given that a = 17.0 L^2.atm/mol2 and b = 0.136L/mol calculate the pressure of isopentane as predicted by the van der waals equation. (b) The elements of group 5A, the nitro

Heat Engine, Net Work, Waste Heat

An inventor claims to have developed a heat engine that receives 750 kJ of heat from a source at 400K and produces 250 kJ of net work while rejecting the waste heat to a sink at 300K. Is this a reasonable claim? Why?

Titration of a Strong Acid

Procedure 1 (click to view assignments for this procedure) PLEASE NOTE: Titration requires several steps in order to obtain exact results. 1. Take a clean Erlenmeyer flask from the Glassware shelf and place it on the workbench. 2. Add 25 mL HCl (of unknown concentration) to the flask. 3. Add 2 drops of phenolphthal