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Physical Chemistry

Positive or Negative Electrolyte Charging

If you have an electrolyte solution in which you have inserted an electrode to charge it either positive or negative - and then you remove the electrode - is it possible to then magnetize this solution by any one or several methods?

Typical Concentration Problems

22. How many grams of potassium permanganate, KMnO4, are required to make 2.00X10^2cm^3of a 1.50M solution? 27. What is the concentration of a solution that contains 90.3g of MgSO4 in 5.00 x10^2cm^3?

Equilibrium - I.C.E. Question

Phosgene, COCl2 (g), is an extremely toxic gas. It was used during World War I. Today it is used to manufacture pesticides, pharmaceuticals, dyes, and polymers. It is prepared by mixing carbon monoxide and chlorine gas. CO (g) + Cl2 (g) = COCl2 (g) <-- the equal sign should be the sign for foward and reversible

Physical Chemistry Questions

1) How many milliliters of 0.480M NaOH would be required to titrate a 5.00ml solution of 0.320M H2SO4? Report answer to the correct number of significant figures. 2) Write a balanced equation for the combustion of octane, C8H18. 3) If the standard enthalpy of formation (deltaHf) of methanol, CH3OH, is -238.6kJ/mol, deltaHf(CO

Gaussian Plume-Qualitative

Explain qualitatively how the following would change the calculated surface concentration of SO2 assuming a gaussian plume from a smoke stack that follows the gaussian equation for the concentration of SO2 i) The wind speed decreased. ii) The wind speed increased. iii) A stable temperature profile became unstable. iv) An

Liquid Phase Oxidation of S(IV) to S(VI) and pH Lowering

Write the reactions responsible for the LIQUID PHASE oxidation of S(IV) to S(VI), and show how the oxidation can lead to a decrease in pH of rain water. I think you can help me with this. Please let me know. I've included all details.Thank you Dr. M. There are two sets of reactions with 3 parts for each set. I'm not sure w

Colligative Properties/Phase Diagrams/Intermolecular Forces

Diagram and explain the H-Bonds if they exist for the following molecules: (a.)H2S, (b.)CH4, (c.)H2SO3, and (d) PH3. Give reasons for the fact that ionic solids as NaCl have high melting points and dissolve readily in water, whereas network solids such as diamond have very high melting points and do not dissolve in water.

Problem involving calculating Pressure

1. If a pressure reading is 20 psi, what is the pressure in foot of water? 2. What is the pressure in psi for a pressure head of 46.2 feet? 3. What is the pressure in psi for a pressure reading, in psi, at the bottom of a 30 feet high reservoir, which has a diameter of 50 feet? 4. What is the pressure in psi of th

Combustion of Sucrose in a Bomb Calorimeter

1. Combustion of 2.016 grams of solid sucrose (C6H12O6) at 25 º C in a bomb calorimeter with heat capacity 9550 J K -1 gives a temperature rise of 3.282 º C. a) Write the balanced equation for the combustion of sucrose b) What is the work done by the system? c) What is the heat change per mole of sucrose for the reaction?

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&#8595;3CHO(g) &#8594; CH&#8595;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


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


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


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,