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Physical Chemistry

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

Quantitative Chemistry Analysis

1) What is the pH of a solution prepared by adding 7.21 mL of 2.14 M NaOH to 1.00 g of hypochlorous acid (HOCl, FW - 52.46, pKa = 7.53), 1.00 g sodium hypochlorite (NaOCl, FW - 74.44) and diluting to 100.0 mL. 2) What mass of solid citric acid (g) and how many milliliters of 0.500 M NaOH are needed to produce 100.0 mL of a bu

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

Potentiometer titration calculation

A 25 ml mixture of HCl-H3PO4 was diluted with 75ml with dH2O, total volume 100ml, and then 25 ml of that was removed and added with 75 ml of dH2O. This mixture was then titrated with 0.1M NaOH, attached is data that was found. What are the molarities of the HCl and H3PO4 in the original solution? First equivalence point

Weight percent for components of mixture

A solid sample weighing 0.2736 g of ethylammonium chloride appreciably contaminated with ammonium chloride (but no other contaminants) required 34.20 mL of 0.08177 M NaOH for complete titration. Find the weight percent of each component in the mixture. This was a problem on a handout that our class got, and I was really not

Gases of Unknown Molecular Masses

Hey. I'm having a lot of trouble with this question. A gas of unknown molecular mass was allowed to effuse through a small opening under constant-pressure conditions. It required 105s for 1.0L of the gas to effuse. Under identical experimental conditions it required 31s for 1.0L of 02 gas to effuse. Calculate the molar ma

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

Compounds to prepare buffers

Prepare 1.00L of a pH~12 buffer with a total phosphate concentration of 0.050 M.You have at your disposal the following compounds Compounds: H3PO4 Ka=7.11*10^-3 FW=97.9950 NaH2PO4 Ka=6.34 * 10^-8 Fw=119.9769 Na2HPO4= ka=4.22*10^-13 fw=141.9588 Na3PO4 Fw=163.9407 Which two compounds would you use to prepare a buffer

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

Vapor Pressure of Ideal Solutions

At 25C the vapor pressures of chloroform and carbon tetrachloride are 26.54 and 15.27 kPa respectively. If the liquids form ideal solutions, (a) what is the composition of the vapor in equilibrium with a solution containing 1 mol of each; (b) what is the total vapor pressure of the system?

Buffer solution Problem to determine pH

1.A buffer solution is prepared which consists of 0.100M HC2H3O2 and 0.100M NaC2H3O2, the dissociation constant, Ka of HC2H3O2 is 1.74 x 10^-5 Determine the pH after the addition of 10.0ml of 0.1M NaOH to 100.00ml of this buffer. 2. An aqueous solution of 100.0ml 0.100M NaCl is titrated with 0.100M AgNO3 (AgCl Ksp= 1

Stoicheometry as Potassium Salts

A 2.9880g sample containing Cl- and ClO4- (as the potassium salts) was dissolved in sufficient water to give 250.0 mL of solution. a 50.00mL aliquot required 13.97mL of 0.08551M AgNO3 to titrate the Cl-. In a second 50.00mL aliquot, the ClO4- was reduced to Cl- with V2(SO4)3. Titration of the reduced sample required 40.12mL of t

Heat Capacity of 2-Propanol

Given the following heat capacity data for 2-propanol, determine the amount of heat required to heat 500 mL of 2-propanol from 0 C to it's boiling point. T CP [K] [J/(mol*K)] 283.15 153.43 293.15 159.79 293.15 160.37 313.15 171.88 333.15 189.41 333.15 190.25 343.15

Virial Equations Expanded

PVm=RT(1+B'p+C'p^2+.....)(the virial equation expanded in pressure) and PVm=RT(1+B/Vm+C/Vm^2+......)(the virial equation expanded in 1/ Vm )are expansions in p and 1/Vm,respectively. Find the relation between B, C and B′, C′.

Balloons and Perfect Gas Law

Balloons are still used to deploy sensors that monitor meteorological phenomena and the chemistry of the atmosphere. It is possible to investigate some of the technicalities of ballooning by using the perfect gas law. Suppose your balloon has a radius of 3.0 m and that it is spherical. (a) What amount of H2(in moles) is needed t

Pressure in a manometer

A manometer consists of a U-shaped tube containing a liquid. One side is connected to the apparatus and the other is open to the atmosphere. The pressure inside the apparatus is then determined from the difference in heights of the liquid. Suppose the liquid is water, the external pressure is 770 Torr, and the open side is 10.0

Conjugate Pairs of Acids and Bases

What is the base if the acid is H2PO4- and the equation of the pair? What is the base if the acid is HPO4-2 and the equation of the pair? What is the acid if the base is F- and the equation of the pair?

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

Stoichiometric Problems

8) If the yield of CO2 (g) from the reaction of butane with hydrogen peroxide is only 80.65%, with how many grams of butane and hydrogen peroxide must you have started if you obtain 26.45 g of CO2? 9) Nickel(II) carbonate is placed into an open container and heated. A given amount of nickel(II) oxide is produced. However, if

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

Preparing a Buffer Solution

Calculate the mass (g) of pure Na3AsO4 (s) and volume (mL) of 1.50 M HCl that are required to make 100.0 mL of a buffer solution at a pH of 6.80 and an H2AsO4-(aq) concentration of 0.100 M. The MW of Na3AsO4 is 207.862 g/mol and for H3AsO4, pKa1 = 2.24, pKa2 = 6.96, and pKa3 = 11.50.

pH of a Buffer Solution of Formic Acid

What is the pH of a solution in which 10g of HCOOH, formic acid, and 10g of HCOONa, sodium formate are combined in 1L of solution? What would the pH be if 10 mL of a 0.10 M solution of NaOH were added to the original solution?

Conjugate Acids and Bases (Ka and Kb)

Given the following acids or bases: 1. H2SO3 2. HPO4 (-2 charge) a. Write the acid reactions for each of the above. b. Write the Ka expression for the reactions and look up the Ka for each of the above. c. What is the conjugate base of each of the above? d. Write the reaction for the conjugate base interacting with wa

pOH, % Ionization, and Ka of a Weak Base

QUESTION 1 If Kb for NX3 is 6.5 x 10-6, what is the pOH of a 0.175 M aqueous solution of NX3? Express your answer numerically. pOH = _____________________________________ Question 2 If Kb for NX3 is 6.5 x 10-6, what is the percent ionization of a 0.325 M aqueous solution of NX3? Express your answer numericall