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    General Chemistry

    Calculating volume of water evaporated

    A 230mL sample of a 0.276 M CaCl2 solution was left on a hot plate overnight; the following morning, the solution is 1.10 M. What volume of water evaporated from the 0.276 M CaCl2 solution?

    Solving a Wave Function

    Question: What is the complete wavefunction for n=2, L=0, and m(sub L)= 0? What radius of the orbital specified is required to contain 95% probability of finding an electron?

    Measuring Water Hardness

    In an experiment for measuring water hardness in a water sample, using Atomic Absorption Spectrophotometry, I obtained a value of 173.74 ppm hardness for my water sample. Using EDTA determination, I obtained a value of 440 ppm hardness for my sample. In both these methods, I was measuring the hardness in relation specifically to

    Hazardous Dyes

    Question: Many dyes used in food products are classified a hazardous chemicals in their pure form. Why then can they be safely used in those food products?

    Kf & vapor pressure

    A soluation of HO-CH2-CH2-OH is prepared by dissolving 651g of ethylene gylcol in 1.50kg of water. Determine the freezing point of the soluaiton and the vapor pressure of water above the solution 25.0 degrees C. The normal freezing point of water is water is 0.00 degrees C with a freezing oint depression constant of 1.86 degr

    General Chemistry Volumes

    5.17 A gas occupying a volume of 725 ML at a pressure of 0.970 atm is allowed to expand at constant temperature until its final volume?

    General Chemistry

    4.60 You have 505 ml of a 0.125M HCI solution , and you want to dilute it to exactly 0.100 M. How much water should you add?

    Molarity Material Calculated

    A quantity of 5.25 g of NaOH is dissolved in a sufficient amount of water to make up exactly 1L of solution. What is the molarity of the solution?

    Jacobians and Polar Coordinates

    Please view the attachment for proper formatting of the question. Question: The range of the polar coordinates are 0 <= r <= ~, 0 <= theta <= pi, and 0 <= phi <= 2pi and the range of the Cartesian coordinates are - ~ < x,y,z, < ~. In the integrals we must relate the two. This is done by the Jacobian, and the result is, d

    Correctly Balancing Equations

    Which, if any, of the following equations is or are correctly balanced? NH4NO3 N2 + O2 + H2O 3Cu + 8HNO3 3Cu(NO3)2 + 2NO + 4H2O 6CO2 + 6H2O C6H12O6 + 6O2 NaOH + Cl2 NaOCl + NaCl + H2O

    Precipitate of AgCl

    Will a precipitate of AgCl form when 0.050 mol NaCl(s) and 0.050 mol AgN0subnumber3(s) are dissolved in 500.0 milliliter of 3.0 mol/Litre NHsubnumber3 solution? (Kf for Ag(NH3)2^+ is 1.5x10^7) Ksp for AgCl = 1.6x10^-10.

    8 precipitate of magnesium flouride

    Will a precipitate of magnesium flouride form when 200.0 milliliter of 1.9x10^-3mol/Litre MgClsubnumber2 solution is added to 300.0 milliliter of 1.4x10^-2mol/Litre NaFsolution? (ksubletterssp(MgFsubnumber2)=6.9x10^-9) Briefly explain by showing your numerical calculations show work. thanks

    Significant Figures - Scientific Notation

    Need to calculate the average of the following two figures, and be sure to keep significant figures. 19.5 + 20.40 = 39.9 39.9 /2 = 19.95 If the answer is 19.95, what is the answer using significant figures only? Can the answer containing significant figures be put into scientific notation?

    Conversion factors

    Convert the following to the required units: 550 uL (microliters) per hour to milliliters per day Please show steps

    Word problem: Convert uL to mL

    A nurse plans to five flu injections of 50 uL (microliters) each from a bottle containing 2.0 mL of vaccine. How many doses are in the bottle? Please show steps to get answer.

    Barium hydroxide

    Write a balanced chemical equation, for the reaction that occurs, when Solid barium hydroxide, dissolves in water. Thank you

    Calculating Vapor Pressure

    The vapor pressure of a solution containing 53.6 g glycerin (C3H8O3) in 133.7 g ethanol (C2H5OH) is 113 torr at 40 degrees Celsius. Calculate the vapor pressure of pure ethanol at 40 degrees Celsius assuming that glycerin is a nonvolatile, nonelectrolyte solute in ethanol.

    Half life

    1) Radioisotopes such as aluminum -26, which is believed to have been present in the solar system when earth was formed but can no longer be detected, are known as extinct radionuclides. The half-life for the decay of aluminum -26 is 7.20 x 10 ^5 years. How many years did it take for 99.99% of the aluminum -26 to decay? If