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Physical Chemistry

Titrations: Finding Mass Percent of Arsenic in a Pesticide

The arsenic in a 1.0211-g sample of a pesticide was converted to H3AsO4 by suitable treatment. The acid was then neutralized and exactly 40.00 mL of 0.05922M AgNO3 was added to precipitate the arsenic quantitatively as Ag3AsO4. The excess Ag+ in the filtrate and in the washings from the precipitate was titrated with 14.76 mL o

partial pressures of SO2 and N2

3.00 g of SO2(g) is originally in a 5.00 L vessel at 21 degrees Celsius and is transferred to a 10.0 L vessel at 26 degrees Celsius. 2.35 g N2(g) is originally in a 2.50 L vessel at 20 degrees Celsius and is transferred to the same 10.0 L vessel. - what is the partial pressure of SO2(g) in the larger container? - what is th

Mass of Nitrogen

Suppose 5.0 liters of Nitrogen (diatomic) is at a temperature of 40 degrees C and a pressure of 1.5 ATM. How many grams are present?

Calculate mass, mole fraction and avg. molecular weight of air

Calculate the constituent (a) mass, (b) mole fraction (c)average molecular weight of air at 25 degree centigrade, 1 atm, and molar density of all listed gases is 24.5 L/mol, and volume air is given to be 100 L. Name Volume fraction N2 0.7808 O2 0.2095 Ar 0.0093 CO2 315

Oxidation Numbers (Oxidation States)

How do I find out the oxidation numbers of: - Ti in TiO2 - N in N2H4 - Cr in Cr2O7 2- <-- the 2- is above the margin, in the same place as if it was to the power of 2- - N in HNO2 - C in C204 2- <-- same as the Cr2O7 - Sn in SnCl3 - <-- same as others, possible -1?

Acid-Base Reactions: Names to Formulas from acid base reactions

What would be the proper balanced molecular and net ionic equations for each of these neutralization reactions? - solid chromium (III) hydroxide reacts with nitric acid - aqueous hypochlorous acid and aqueous calcium hydroxide react - aqueous acetic acid is neutralized by aqueous potassium hydroxide

reversible or irreversible process

An ideal gas expands isothermally from state A to state B at 300K with an entropy change (deltaSsys) of 50 J/K. When the expansion was performed, the work done by the system was - 6 kJ/K. Was this process reversible or irreversible? Explain.

Convert to mg/L from Molarity

Convert to mg/L using dimensional analysis: 1. 0.01 N Ca+2. Here is additional info: salt is CaCl2 2. 1M HCO3 3. 0.02 N H2SO4 4. 0.02 M SO4 2- (i.e)sulfate ion

density of liquid methanol

Determine the density of liquid methanol in (lb/ft^3) and convert heat capacity, thermal conductivity and viscosity from SI units to English Units. Given: Specific gravity= 0.92 at 60 degree F Density of reference substances (Water)= 62.3 lb/ft^3 Heat capacity=0.61 cal/(gram degree centigrade) at 60 degree F Thermal Condu

Number of exhaled molecules

Total mass of the atmosphere is equivalent to that in a layer 7 kilometer deep with density equal to the density at the surface. Assuming that air is uniformly mixed, how many molecules of air you have exhaled in the last 20 years will be inhaled in a single breath? Given: Earth's surface area=5.11*10^9 square kilometers Vo

pH and molar concentration of hydrogen ion

1.Given the molar concentration of hydrogen ion [H+] = 6.2 x 10 -7, calculate the concentration of hydroxide ion. 2.Given the molar concentration of hydroxide ion [OH -] = 4.6 X 10 -13, calculate the concentration of hydrogen ion. 3. In 1 mL of water there are 3 X 1022 molecules of H2O. How many hydrogen ions are in 1 mL o

Empirical Formulation of a Compound

16. A compound contains 40.00% carbon, 6.67% hydrogen, and 53.33% oxygen. Determine the empirical formula of the compound. Please help with the following problems. 1. Give the chemical formula for calcium phosphate. 2. A hypothetical element, Js, has three naturally occurring isotopes. The atomic mass and relative abunda

Gasoline in a Tank: Determine Pressure, Density, & Force

The gasoline storage tank is filled to 12m and the closed space above is filled with nitrogen gas N2. For the condiction shown (see attachment) determine : a) Pressure of nitrogen gas b) Density of gasoline c) Force on the tank bottom d) Force on the flat door e) Minimum force to hold door closed.

Energy Changes Due to Pressure and Temperature Changes

1. a volume of 20 cu ft of air at pressure of 50 psig is heated and expanded to 30 cu ft and 40psig find the change in the energy of air in joules. (A)35564 j (B) 48219 j (C)123378 j (d)167278j 2>A quantity of gas equal to 35 cu ft is to be expanded adiabatically.It has specific heat at constant pressure of 0.532 and

Expansion of Nitrogen - Ideal Gas Law

A sample of nitrogen gas has a volume of 3.00 L at 25 degrees C. What volume will it occupy at each of the following temperatures if the pressure and number of moles are constant: a) 546K b) 273K c) 373K

Acid-base titration & analytical chemistry

A 0.213-g sample of uranyl(VI)nitrate, UO2(NO3)2, is dissolved in 20.0 mL of 1.0 M H2SO4 and shaken with Zn. The zinc reduces the uranyl ion, UO2 (with a charge of 2+), to a uranium ion, Un+ (where n+ is the charge of the uranium ion). To determine the value of n, this solution is titrated with KMnO4. Permanganate is reduced to

Acid according to Lewis, but not according to Bronsted

Please see the attached file. 2. Balance this equation using no fractional coefficients H2O + CrO4^2- + HSnO2- ---> HSNO3- + CrO2- + OH- 3. Balance this equation using no fractional coefficients MnO4- + H2O2 + H+ --> Mn2+ + O2 + H2O 4. Which is an acid according to Lewis, but not according to Bronsted? OH- O2- CO2

empirical formula and molecular formula

2) Two substances Q and R each have the elemental composition C = 60% h=13.3% 0=26.7% by mass 0.60 grams of each substance occupied a volume of 0.336 liters at 137 Celcius and standard pressure a) Calculate the empirical formula and the relative molecular mass of Q and R. B) What is the molecular formula

Pressure of Dry Butane Gas

I am working on a Chemistry lab write up and I have to determine the pressure of the dry butane gas. My Data Table: initial mass of lighter= 21.03g volume of gas collected= 93.6 mL temperature of the water= 23.2 degrees C barometric pressure= 1.012 atm final mass of lighter= 20.820 therefore the mass of butane collec

Positive or Negative Electrolyte Charging

If you have an electrolyte solution in which you have inserted an electrode to charge it either positive or negative - and then you remove the electrode - is it possible to then magnetize this solution by any one or several methods?

Typical Concentration Problems

22. How many grams of potassium permanganate, KMnO4, are required to make 2.00X10^2cm^3of a 1.50M solution? 27. What is the concentration of a solution that contains 90.3g of MgSO4 in 5.00 x10^2cm^3?

ICE Problem: Calculate Final Concentrations

Phosgene, COCl2 (g), is an extremely toxic gas. It was used during World War I. Today it is used to manufacture pesticides, pharmaceuticals, dyes, and polymers. It is prepared by mixing carbon monoxide and chlorine gas. CO (g) + Cl2 (g) = COCl2 (g) <-- the equal sign should be the sign for forward and reversible re

Physical Chemistry Questions

1) How many milliliters of 0.480M NaOH would be required to titrate a 5.00ml solution of 0.320M H2SO4? Report answer to the correct number of significant figures. 2) Write a balanced equation for the combustion of octane, C8H18. 3) If the standard enthalpy of formation (deltaHf) of methanol, CH3OH, is -238.6kJ/mol, deltaHf(CO

Rate of S(IV) to S(VI) at Different pHs using O3 and H2O2

If the ozone concentration in the plume is 80 ppb, calculate the liquid-phase rate of S(IV) oxidation in the plume by ozone. The rate for the oxidation of SO2 by H2O2 is given by the expression: please see attachment for expression. where k = 7.45 &#61620; 107 M-2 s-1 and K = 13 M-1. If the pH of the rainwater is 4.3, ca

Gaussian Plume-Qualitative

Explain qualitatively how the following would change the calculated surface concentration of SO2 assuming a gaussian plume from a smoke stack that follows the gaussian equation for the concentration of SO2 i) The wind speed decreased. ii) The wind speed increased. iii) A stable temperature profile became unstable. iv) An