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Physical Chemistry

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

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

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

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

Moles of Aluminum, Sulfur and Oxygen Atoms

Calculate the number of moles of aluminum, sulfur, and oxygen atoms in 8.00 of aluminum sulfate, . Express the number of moles of Al, S, O, and atoms numerically, separated by commas. Calculate the number of moles of magnesium, chlorine, and oxygen atoms in 8.40 of magnesium perchlorate, . Express the number of moles o

Calculate the standard emf for each of the following reactions

1. Calculate the standard emf for each of the following reactions: a)H2(g) + F2(g)---> 2H+(aq) + 2F-(aq) b)Cu(s) + Ba 2+(aq)---> Cu 2+(aq) + Ba(s) c)3Fe 2+(aq)---> Fe(s) + 2Fe 3+(aq) d)Hg2 2+(aq) + 2Cu+(aq)----> 2Hg(l) + 2Cu 2+(aq) 2. The standard reduction potential for the reduction of RuO4-(aq) to RuO4 2-(aq) is +0

Evaluating Receptor/Ligand Binding

3. Evaluating Receptor/Ligand Binding as a Reversible Mixed Second-Order Reaction The solutions for reversible binding between receptors and ligands to form complexes, R + L C, when ligand is in excess are: where the equilibrium dissociation constant and relaxation time are defined as and , respectively. a.

Solubility of a Salt & "Salting In"

Solubility of a Salt & "Salting In" The solubility product of the sparingly-soluble salt Ag2S in water, at 25 C, represents the reaction: 2 Ag(s) + S(rh)  Ag2S(aq) where silver sulfide dissociates completely into silver and sulfide ions upon dissolution in water. Here S(rh) stands for rhombic crystalline solid su

Partition coefficient in solvent extraction

Problem: Given that the partition coefficient for a solute is K in a water-ether solvent extraction system, is it more effective to do one extraction with V mL of ether or three extractions with V/3 mL of ether. Assume that the volume of water in the system to be V0 mL

Proteins and enzymes

1- Write a brief paragraph that explains the buildup of proteins from amino acids to the final quaternary structure of the protein. 2-Describe how the structure of an enzyme is essential to its functioning. 3-What is the fundamental relationship between nucleic acids and protein synthesis? 4-ATP is the most common stor

Precipitation Titration of Cobalt Chloride

LEASE NOTE: Titration requires several steps in order to obtain exact results. The procedures described in this lab assume that you have already done the TITRATION TUTORIAL and are familiar with the technique. 1. Take a 150 mL Erlenmeyer flask from the Glassware shelf and place it on the workbench. 2. Add 10 mL of cobalt c

Rate Law mechanism observed

The rate law for the Br—- catalyzed reaction Br- C6H5NH2 + HNO2 + H+ C6H5N2+ + 2H2O is observed to be rate = = k [H+][HNO2][Br -]. A proposed mechanism is k1 (1) H+ + HNO2 H2NO2+ (rapid equilibrium) k-1 k2 (2) H2NO2+ + Br-

Debye Temperature for Crystalline Solids

Many crystalline solids have constant pressure molar heat capacities at low temperature that obey the Debye T3-Law, which is where R is the ideal gas constant and TD is a constant characteristic of the material known as the Debye temperature. This equatio

Quant problems

1.In the laboratory you have prepared various reagents for your experiments. briefly describe the preparation of 3.00 L of 0.150 M H3PO4 from concentrated commercial reagent. This reagent if 86.0% H3PO4 and has a density of 1.84g/mL. The molar mass of H3PO4 is 97.995 g/mol 2. The following data were obtained for the determina

Wet and dry basis sample questions

3. 10 kg of food at a moisture content of 320% dry basis is dried to 50% web basis. Calculate the amount of water removed. 4. A batch of 5 kg of food product has a moisture content of 150% dry basis. Calculate how much water must be removed from this product to reduce its moisture content to 20% wet basis. 5. A liquid prod

Quant Titrations Calculations

EDTA I Calculate pFe2+ at Ve in the titration of 25.00 mL of 0.02026 M EDTA by 0.03855 M Fe2+ at pH 6.00. EDTA II A sample contained Ni and Zn ions as the only metals that would bind to EDTA. A 50.0 mL solution of Ni2+ and Zn2+ was treated with 25.0 mL of 0.0452 M EDTA to bind all of the metal. The excess unreacted EDTA

Conversion Factor to SI Units

25. A meal replacement product was formulated to contain 380 mg Na per serving. If NaCl was used to achieve the intended Na level, and if this NaCl contained 100 ppm iodine, calculate the micrograms (to the nearest microgram) of iodine per serving in the finished product. Show your work. 26. An evaporator is used to concentr

Chemistry: molar solubility, hydroxide concentrations, ph level

The Ksp of La(IO3)3 is 1.0×10-11. Using activities, what is the molar solubility of La(IO3)3 in a 0.050 M solution of NaNO3? Using activities, calculate the hydroxide concentration in a saturated solution of iron (II) hydroxide in 0.010 M magnesium nitrate. The Ksp for Fe(OH)2 is 7.9×10-16, assume that Mg(NO3)2 dissociates

Solution Concentration Calculations

I.Solution Preparation A.For this experiment, you must calculate the mass of solute, nickel (II) nitrate, needed to prepare the four following standard solutions: 1.0.050 M Ni(NO3) 2in a 100 mL volumetric flask. 2.0.100 M Ni(NO3) 2in a 100 mL volumetric flask. 3.0.150 M Ni(NO3) 2in a 100 mL volumetric flask. 4.0.200 M

Alcoholic Beverage and Clostridium Botulinum Spores

23. When making an alcoholic beverage, such as beer and wine, Brix is a measurement used to assess the amount of sugar present in the fermentation matrix or grape juice. For practical purposes, the fermented product is water and sugar plus alcohol. Each degree Brix is equivalent to 1 percent of sugar in the juice. The alcohol co

Chemistry Combustion Sample Calculation

A 32.2 mg sample of the organic compound from problem 1 was treated to combustion analysis which yielded 59.2 mg CO2 and 12.3 mg of H2O. Analysis by low resolution mass spectrometry yielded a molar mass of 191 g/mol for the pure compound. Further analysis showed that the compound contained only carbon, hydrogen, oxygen, and chl

Quantum Titration Problems

Find the pH of a solution prepared by dissolving all of the following compounds in one beaker and diluting to a volume of 1.00 L: 0.180 moles acetic acid (pKa=4.75), 0.180 mole sodium acetate, 0.060 mol H2SO4, and 0.060 mol NaOH. Assume sulfuric acid dissociates completely (i.e. it is a strong acid). Consider the titration o

Sample Chemistry Problems

A sample containing 0.2784 grams of sodium chloride (NaCl) and 0.5486 grams of magnesium chloride (MgCl2). The chloride in the sample was precipitated by the addition of 47.8 mL of a silver nitrate solution. What is the concentration of the silver nitrate solution? A sample of ore containing manganese weighed 1.2354 grams. Th

Density, Conversions and Significant Figures

1. a: A cube of osmium metal 1.500cm on a side has a mass of 76.31 g at 25*C. What is its density in g / cm3 at this temperature? B: The density of titanium metal is 4.51 g / m3 at 25*C. What mass of titanium displaces 65.8 mL of water at 25*? C: The density of bezene at 15 *C is 0.8787 g / mL. Calculate the mass of

Percent Mass and Stoichiometry

1) You are the science officer on the Starship Enterprise. The ship is circling a new planet. The away team comes back with some rocks and minerals. Some of the minerals contain iron and you want to determine the amount of iron in the sample. You take 9.000 g of this mineral and treat it with excess bromine (bromine reacts wi