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Physical Chemistry

Empirical Formula of a Compound and Conversion

The characteristic odor of pineapple is due to ethyl butyrate, a compound containing carbon, hydrogen, and oxygen. Combustion of 2.78 mg of ethyl butyrate produces 6.32 mg of CO2, and 2.58 mg of H2O. What is the empirical formula of the compound? Please convert from mg to g.

Containers of Water Diluted

Please see the attachment for a visual depiction of the containers. Please calculate the dilution factors for all five containers and show all the work. Thanks! Five containers of water, numbered 1 to 5, are placed in a line: Container #1 contains 5 ml of water. Container #2 contains 1 ml of water. Container #3 contains

Rate Limiting Steps in Metal Oxide Epitaxy

On the bottom right-hand side of the third page of the pdf attached (page 2 of the article), the author states: "Metal deposition rates are easily converted into the oxide growth rate under the assumption that the metal arrival rates are the rate limiting steps, which is true for growth under oxygen- rich conditions." I am

Dilution Factors & Serial Dilution

Seven test ubes each containing 4.5 ml of water are lined up. 0.5 ml of yeast culture is pipetted in to test tube #1. Then 0.5 ml of the solution form test tube #1 is pipetted into test tube #2. Then 0.5 ml of the solution for test tube #2 is pipetted into test tube # 3 and so on until 0.5 ml of the solution from test tube #6

Thermodynamic Calculations for Ideal Gases

One mole of an ideal gas a 273.15 K is allowed to expand isothermally from 10.0 MPa to 1.00 MPa. Make a table to show your answers for the following questions. (Show your work - the subscript m indicates the value per mole.) - View attached document to see questions a)-d).

Empirical and Molecular Formula of Cadaverine

Cadaverine, a substance produced by the action of bacteria on meat, contains 58.55% C , 13.81% H , and 27.40% N. Determine the empirical and molecular formulas. Please provide detailed explanation.

Working with Temperature and Gas

1. What is the final temperature if 25 mL of milk 3.0 degrees Celsius is mixed with 150 mL of coffee at 95 degrees Celsius? Start by writing the equation that shows conservation of energy. State any assumptions you make. 2. If the temperature is raised sufficiently high, proteins, DNA, and RNA will actually begin to unfo

Boiling point elevation and freezing point

Calculate the boiling-point elevation of a solution made from 15.0 g of a nonelectrolyte solute and 250.0 g of water. The molar mass of the solute is 50.0 g and Kb=0.51°C/m. Consider a solution of 50g KCl, a strong electrolyte, dissolved in 1.5 kg of water. Determine the expected freezing point of the solution. The molar mas

Dilution and Colony-Forming Units

Ten grams of hamburger were added to 90 mL of sterile buffer. This was mixed well in a blender. One-tenth of a mL of this slurry was added to 9.9 mL of sterile buffer. After thorough mixing, this suspension was further diluted by successive 1/100 and 1/10 dilutions. One-tenth of a mL of this final dilution was plated onto Plate

Ionisation of Diacetylmorphine/Heroin

I have learn't that the pKa of diacetylmorphine is 7.6, close to physiological pH and hence will be mostly un-ionised in the blood. 1. How can diacetylmorphine be ionised in the blood and what will the effects of this be on the molecule in circulation? (I assume that it will be more soluble?) 2. When HCl is added to diace

Change in volume: scuba diving

When scuba diving, it is important to come back to the surface of the water from deep dives slowly. If this does not happen, then the diver can get the ?bends?. Determine the amounts of N2 and O2 dissolved in 7.5 L of blood at 298 K at a depth of 100.0 feet below the surface of the water. What is the total volume of dissolved ai

Dissociation Reactions for Non-Standard Amino Acid

1) Draw the dissociation reactions for the non-standard amino acid drawn below. Using lysine as a model estimate the pKas for all the possible dissociation's. Justify your estimates by discussing factors that raise and lower pKas.

Arrhenius equation

** Please see the attached file for the complete solution ** The unimolecular decomposition of urea in aqueous solution is measured at 2 different temperatures and the following data are observed: Trial # Temp (C degrees) k (s-1) 1 60 1.2 X 10^-7 2 71.5 4.40 x 10^ -7 Determine the Arrhenius para

Questions Regarding Combustion Reactions

Please help with the following problems: A fuel has the following weight percentage composition: C = 52%, H = 11%, S = 0%, O = 9%, moisture = 13%, Ash = 15% 100 kg of this fuel is burned and you need to calculate the mass of oxygen required for this combustion reaction to occur. (The 'fuel' is an un-named carbon-hy

Physical Chemistry: Rate Law

The following reaction A(g) + B(g) →C(g) the mechanism is postulated to occur by way of the mechanism below: Step 1. A(g) k-1↔k1 M(g) Step 2. M(g) + B(g)k2 →C(g) ————————————— Overall A(g) + B(g) →C(g) Use steady state approximation to express the rate law in terms of reactants A and

Determine the glucose tolerance of two different patients by generating and using a standard curve to calculate the amount of glucose in their blood before and after eating.

This lab provided a 100mM Glucose standard solution which you are required to dilute with water to give final concentrations of 0,0.4,0.8,1.2,1.6 and 2.0 mmol/L glucose in a final volume 0.5ml. You will then use those concentrations to generate a standard curve using a spectrophotometer in order to calculate the amount of glucos

Calculating the Equilibrium Constant: Change in Free Energy

Survey of physical chemistry State all of the assumptions (e.g. ideal gas etc). (previous reaction is 2H??2(g) + O2(g) ----> 2H2O(g)) Given the reaction in the previous question at 298 Kelvin where H2 has a partial pressure of 0.10 bar, O2 is at 0.20 bar, and H2o is at 1.5 bar: (a) Determine the direction and quantif

Survey of Physical Chemistry Assumptions

Survey of Physical Chemistry 5th Edition State all assumptions (e.g. ideal gas etc). Using the tables in your text, calculate the following reaction under constant pressure (1 bar) at 298 Kelvin, calculate th e Î"S0 , Î"HO, and Î"Go , for the following reaction. Is this reaction spontaneous at room temperature? Can th

Working with an ideal monoatomic gas

(from 'Survey of Physical Chemistry', 5th edition) Calculate the Î"S for a gas in a closed system that is an ideal monatomic gas initially at P= 5 atm, V=5L, and T = 310 K which expands to V= 10 L and its temperature is increased to 390 K.

Molarity

Is molarity the most representative form of quantifying acids and bases? Discuss the possible disadvantages of this system and the alternatives to the same.

Dilution Problems

See attachments.

Problem Statement

A 40-year-old manager, at a prominent legal firm in L.A., experiences abdominal pain post lunch. He goes to the restroom a couple of times, but continues to experience pain and cramps. He eventually decides to get himself examined. While questioning him, you learn that he consumed two bottles of beer at lunch. The alcohol (ethyl

Determine pH of a Solution: Henderson HasselBach Equations

Using a ICE table (initial change equilibrium) a) Calculate the pH of solution that is 0.175M in acidic acid(HC2H3O2) ans 0.110Min potassium Acetate(KC2H302) b) Perform same calculation using the Henderson HasselBach equations to determine pH of the solution

Chemistry Sample Question: Buffer Solution pH Calculation

1.00L buffer solution contains 0.100M acetic acid and 0.100M sodium acetate. The ka of acetic acid is 1.8*10^-5. Calculate the pH of this buffer solution after the addition of 0.010 moles of solid sodium hydroxide to the buffer

Salt

A freshman is currently enjoying the Arts Studio program she is pursuing at a well-known university. In her free time, she likes to skate, take salsa dance lessons, and cook. She particularly enjoys pickling and decides to pickle olives over a leisurely weekend. According to the recipe, she needs to add three teaspoons of salt t

Properties of Temperature, Heat and Their Relationship

What is Heat? What is temperature? What are the various properties that account for temperature? What are the various sources of heat? What is the relationship between heat and temperature? How are they different?

Determining Copper in Brass

1st I titrated Na2S2O3 and determined the molarity to be 0.164. I am having trouble with the calculations for the dissolution of brass. Method Weighed out 0.3026 g of an unknown barass, placed in a 250 mL Erlenmeyer flasks. In fume hood, add 5 mL of 6M HNO_3. Warm the solution on a hot plate until dissolution is complete. Wh

Standardization of Na2S2O3

Added 0.12 g KIO3 and dissolved in 75 mL of distilled water. Added .20 g of KI to solution, then added 10 mL of 1M HCl and immediately titrated with thiosulfate solution (made by weighed 25 g of Na2S2O3-5H20 and .1 g of Na2C3 in 1 L of H20 that has been boiling for at least 5 minutes, then cooled solution)added 5 mlo of starch

Redox Titration

Would you help me to sort out this question? A 3.026 gram portion of Cu(II) salt was dissolved in a 250 ml volumetric flask. A 25.0mL aliquot was analyzed adding 1 g KI and titrating the liberated iodine with 23.33 mL of 0.04668 M Na2S2O3. Find the weight percent copper in the salt.

Calculating percent purity from a reaction

One of the reactions that occurs in a blast furnace, where iron ore is converted to cast iron is Fe2O3 + CO = Fe + CO2. Suppose that 1750 kg of Fe is obtained from a 2780 kg sample of Fe2O3. Assuming that the reaction goes to completion, what is he percent purity of Fe2O3 in the original sample? I balanced the equation to ge