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    Stoichiometry

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    Calculating the Mass of Compounds

    Please view the attached file to see the various compounds I need to calculate the mass of. I am having some difficulty approaching these questions.

    Empirical formula of unknown compound

    A major oil company has used a gasoline additive called MMT to boost the octane rating of its gasoline. What is the empirical formula of MMT if it is 49.5% C, 3.2% H, 22.0% O, and 25.2% Mn? empirical formula_______________________________

    Molarity

    5. Calculate the sodium ion concentration when 60.0 mL of 6.0 M sodium carbonate is added to 30.0 mL of 1.0 M sodium bicarbonate.

    Solubility Product and Solubility

    The solubility product of silver chromate, Ag2CrO4, at 25 degrees Celsius is 4.05 x 10^-12 mol^3/L^3. Calculate the solubility of silver chromate in: a) pure water b) 0.0500 M silver nitrate solution c) 0.0500 M potassium chromate solution

    Calculating concentration in a solution

    A student pipets 20.00mL of 0.030M Na2SO3 soln. into a large beaker. To this same beaker the student adds 30.00 mL of 0.020M KIO3 soln. and 50.00 mL of distilled water. The student mixes it thoroughly with a stir rod. Calculate the concentration of Na2SO3 and KIO3 in the new solution but before the reaction occurs.

    Boiling Point Elevation

    I'm doing boiling point elevation and the formula is: deltaT_b = k_b * m * i (k_b = 0.52 degrees C/m for water) I don't know how to use this calculation with this problem: Calculate the boiling point of an aqueous solution containing 3.8% by mass of NaCl. Do I take 3.8% of NaCl's mass of 58.44g? How do I set up the equatio

    Electrochemical cell

    It is given that the electrochemical cell is at 298K. At time zero [Zn 2+ ]= 1.0 x 10 ^-3 M and [Ag +] = 0.500 M. Calculate the molarities of zinc and silver ions after a current of 2.00 amperes flow for 20 hours. Please show step by step and the units you are using.

    Density of Oil Functions

    If a serving of oil is exactly 1 tablespoon, which has a mass of 14g, and there are 96 servings in the container, what is the density of the oil in grams per milliliter (g/ml)?

    Density

    A cylindrical bar of gold that is 1.5 in. high and 0.25 in. in diameter has a mass of 23.1987g, as determined on an analytical balance. An empty graduated cylinder is weighed on a triple beam balance and has a mass of 73.7g. After pouring a small amount of liquid into the graduated cylinder, the mass is 79.16g. When the gold cyl

    Chemistry Problems

    1. The following reaction occurs: CaCO3 + 2H- -> Ca2+ + CO2 +H2O If a 25gm sample of calcium carbonate is added to a 75.5 ml HCl (density = 1.125gm/cm3, 26% HCl by mass), calculate the molarity of the HCL remaining in solution (if any) after the reaction is complete. Assume no volume change. 2. A sample of coc

    Concentration of an ideal solution

    An ideal solution with solute density 1.05 and solvent density 1.00 is subject to a huge gravity force field, a linear function of postition, F=kr, k is a constant and r is the position along the field. Derive the concentration as a function of T and position r along the field. (Hints: express gravitational potential as functi

    Finding limiting reactant, theoretical yield, and actual yield

    An electric furnace produces phosphorus by the following reaction: Ca3(PO4)2(s) + C(s)+SiO2(s)= CaSiO3(s)+CO(g)+P(I) An initial reaction mixture contains 1500g calcium phosphate, 250 g carbon and 1000g silicon dioxide. a) What is the limiting reactant? b) What is the theoretical yield of phosphorus? c) After the reaction

    Determine concentrations in mixture using determinants

    Please see attachment. A solvent called "mixed xylenes" contains the o-xylene, m-xylene, p-xylene and ethyl benzene. In the table below, the absorbances of each of the pure components and the absorbance of a sample of "mixed xylenes" were measured at four different wavelengths. All measurements used the same cell and, theref

    Oxygen production

    The following reaction is used in laboratories to produce oxygen: 2 KClO3 --> 2 KCl + 3 O2 At 25 degrees Celsius and one atmosphere pressure, how many liters of O2 gas will be produced from the reaction of 275g of KClO3?

    Physics

    Imagine that we give N2(+), O2(+) and (NO)+ ions the same velocity of 30.0 km/s and then send them into a mass spectrometer where the magnetic field strength is B=8.5MN/C. How far would the spot on the photographic plate be from the entry point for each ion, assuming that each ion completes one-half of an orbit. The atomic mas

    Determine Concentration of Potassium Chromate to Use (Mohr Titration)

    A titration of 0.100 M Cl^- with 0.100 M Ag^+ used an end point where silver chromate gives an orange precipitate. Select the concentration of potassium chromate that must be present so the orange-colored silver chromate precipitate will appear just when 99.5% of the chloride has been precipitated. Given: Ksp of AgCl = 1.0 x 10

    Oxygen reactions

    Oxygen can be preparead in a lab by the reaction: 2KCLO3 = 2H2(g) + O2(g) Question: How many grams of KCLO3 must be reacted to produce 100 g of O2?

    Daltons Law of Partial Pressures

    Dry air near sea level has the following composition by volume: N_2, 78.08%; O_2 20.94%; Ar, 0.93%; CO_2 0.05%. the atmospheric pressure is 1.00 atm. calculate the partial pressure of each gas in atm and the concentration of each gas in moles per liter at 0 degrees C.

    Gas stoichiometry

    C2H5OH burns in air: C_2H_5OH(l)+O_2 --->CO_2(g)+H_2O(l) balance the equation and determine the volume of air in liters at 35.0 C and 790 mmHg required to burn 227 g of ethanol. assume that air is 21.0 percent O_2 by volume.

    the percent silver of the dime in the oxidation reaction

    For my AP chemistry lab, I was supposed to find the percent of silver in a dime. I started out with the formula: Ag + NaCl → AgCl +Na. The dime was put in a covered beaker with NaCl. However, during the experiment oxygen was added as one of the reactants, accidentally. The precipitated silver chloride was obviously con

    Mass percentage of sodium chloride in a mixture

    A sample of a mixture containing only sodium chloride and potassium chloride has a mass of 3.5650g. When this sample is dissolved in water and excess silver nitrate is added, a white precipitate (silver chloride) forms. After filtration and drying, this precipitate has the mass 7.9143g. What is the mass percentage of sodium ch

    Calculating PPM Saline Solution

    The chloride in a saline solution was determined by the Volhard method. A 25 ml aliquot of the solution was acidified with 2 ml of dilute HNO3 and treated with 25 ml of .1749 M AgNO3 (fw 169.9), causing precipitation of AgCl. After addition of several ml of nitrobenzene, the solution required 26.40 ml of .1575 M KSCN to reach t