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Physical Chemistry

Buffers, Acids, Bases, Salts, Ka and Kb

QUESTION 1 Imagine that you are in chemistry lab and need to make 1.00L of a solution with a pH of 2.50. You have in front of you: - 100mL of 7.00x10-2 M HCl - 100mL of 5.00x10-2 M NaOH, and - Plenty of distilled water. You start to add HCl to a beaker of water when someone asks you a question. When you return t

Mass and Moles of Elements

To do this assignment, use your calculator to do the calculations required. Then invert the calculator to read the message word. Insert the message word into the appropriate space in the statement. Round off all atomic masses to the nearest whole number before using them. When handing in your assignment, be sure to show all

Using Equilibrium to Calculate Product

At low to moderate pressures, the equilibrium state of the water gas shift CO (g) + H2O (g) CO2 (g) + H2 (g) reaction is approximately described by the relation kp = (see attached file) The feed to a continuous shift reactor contains 30 mol% CO, 10 mol% CO2, 40 mol% water and the balance an inert gas. Th

Confirmatory Experiments : Freezing Point Depression and Solubility Tests

The purpose of lab this week is to do "comfirmatory experiments" that further explore the properties of your unknown compound and confirm that it reacts appropriately for the compound you predicted it to be at the end of lab last week. 1. Suppose your unknown is sodium acetate. When a solution of calcium chloride is adde

Heat Created by the Fermentation and Combustion of Glucose

Please help with the following physical chemistry problem: Alcoholic fermentation by microorganisms involves the breakdown of glucose into ethanol and carbon dioxide. C6H12O6 (s) -->; 2 C2H5OH (l) + 2 CO2 (g) a) Calculate the amount of heat liberated in a yeast brew upon fermentation of 1 mol of glucose at 25 °C and 1

Titration and Molarity Questions

Part A. Standardization of the 0.02 M KMnO4 solution with Fe(NH4)2(SO4)2 ? 6H2O. (Molecular weight of the ferrous sulfate hexahydrate is 392.16 g/mol). If you weigh out 1.01 g of the Fe(NH4)2(SO4)2 ? 6H2O, how many moles of iron (Fe+2) are in the sample? Part B Assume you fill a buret with your KMnO4 solution and the v

Meaning, use and calculation of empirical formulas

In this introduction are given the explanation of how to find out an empirical formula if one has found out the chemical elements of an unknown substance and measured their ratio of masses. Also, it is described how one can calculate the ratio of masses from a given empirical formula. Two examples and the explanation of the pri

Molar Concentration of Copper (II) Nitrate

Please help with the following problem. Provide step by step calculations in this answer. A 25.00 mL sample containing Cu2+ gave an instrument signal of 23.6 units (corrected for a blank). When exactly 0.500 mL of 0.0287 M Cu(NO3)2 was added to this solution, the signal increased to 37.9 units. Calculate the molar concentrat

Heat Required to Convert Solid Benzene

The molar heat capacity of C6H6(l) is 136 J/mol x degrees centigrade and of C6H6 (g) is 81.6 J/mol x degrees centigrade. The molar heat of fusion for benzene is 9.92 kJ/mol and its molar heat of vaporization is 30.8 kJ/mole. The melting point of benzene is 5.5 degrees centigrade, its boiling point is 80.1 degrees centigrade and

pH and molar concentration of hydrogen ion

1.Given the molar concentration of hydrogen ion [H+] = 6.2 x 10 -7, calculate the concentration of hydroxide ion. 2.Given the molar concentration of hydroxide ion [OH -] = 4.6 X 10 -13, calculate the concentration of hydrogen ion. 3. In 1 mL of water there are 3 X 1022 molecules of H2O. How many hydrogen ions are in 1 mL o

Empirical Formulation of a Compound

16. A compound contains 40.00% carbon, 6.67% hydrogen, and 53.33% oxygen. Determine the empirical formula of the compound. Please help with the following problems. 1. Give the chemical formula for calcium phosphate. 2. A hypothetical element, Js, has three naturally occurring isotopes. The atomic mass and relative abunda

Expansion of Nitrogen - Ideal Gas Law

A sample of nitrogen gas has a volume of 3.00 L at 25 degrees C. What volume will it occupy at each of the following temperatures if the pressure and number of moles are constant: a) 546K b) 273K c) 373K

Acid-base titration & analytical chemistry

A 0.213-g sample of uranyl(VI)nitrate, UO2(NO3)2, is dissolved in 20.0 mL of 1.0 M H2SO4 and shaken with Zn. The zinc reduces the uranyl ion, UO2 (with a charge of 2+), to a uranium ion, Un+ (where n+ is the charge of the uranium ion). To determine the value of n, this solution is titrated with KMnO4. Permanganate is reduced to

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.

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?

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. .

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