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Physical Chemistry

Percent by Mass

Determine the percent by mass of all the elements in the compound cobalt III acetate.


How would you prepare a liter of "carbonate buffer" at a pH of 10.10? Ka = 4.2 times ten to the negative 7(carbonic acid) Ka = 4.8 times ten to the negative 11(bicarbonate ion) It says the key to solving the problem is picking the correct Ka value. How do I know which one to work with?

Find Delta Smix, Delta Gmix, Delta Hmix, and Delta Vmix

Find delta Smix, delta Gmix, delta Hmix, and delta Vmix if 125 g of benzene and 25 g of naphthalene are mixed at 60 degrees C. Assume the solution to be ideal. The molecular weights of benzene and naphthalene are 78.12 g/mol and 128.19 g/mol respectively.

AP Chemistry Test Review: Gases

(See attached file for full problem description) --- 31. A sample of H2 gas occupies 615 mL at C and 575 mm Hg. When the gas is cooled, its volume is reduced to 455 mL and its pressure is reduced to 385 mm Hg. What is the new temperature of the gas? 54. Hydrogen can be made in the "water gas reaction." If you

Blending of Wines with Acid

I need some help with this question: Two wines are available for blending: One tank of 1000 L has a Titratable Acidity of 9.0 g/L and another tank containing 2000 L has a Titratable Acidity of 0.6 g/L. How much volume do you need to blend to make the 9.0 g/L Titatrable Acid wine equivalent to 7.2 g/L? What is the final volu

Calculations with Ideal Gas Laws

I need to find a simple way to convert gases expressed as mol % to volume percent. Pressure and temperature are constant. For example, what volume percent would water vapour be if given as 1.52 mol %?

Heat Capacity of a Gas

The heat capacity of a gas is given by Cp=a+bT where a and b are constants: a) Determine delta S for heating the gas from T1 to T2 at constant P b) Determine delta G for heating the gas from T1 to T2 at constant P HINT: the integral lnx dx= x ln x-x

Entropy change delta for argon gas

Find the entropy change delta for argon gas undergoing the following temperature and pressure changes: good Ar(g),P=1 atm, T=300 K------> Ar(g), P=10 atm, T=500K

Delta G

Consider the reacton: 2 H2(g) + O2(g) -------> 2 H2O(g). Determine delta G for this reaction at 1000 K.

Ions being reduced or oxidized

*** Please see file for full description*** 1. Into each of three potatoes insert 1 copper and 1 zinc probe. The probes should be inserted to a medium depth inside the potatoes and should be spaced within about an inch of each other. The probes should NOT touch inside or outside of the potato. IMPORTANT: To illuminate an

Assorted AP Chemistry Questions

Consider the reaction. Mn3N2 (s) +H2O (l) → Mg(OH)2 (s) + NH3 (g) a) Balance the equation and name each compound. b) How many moles of Mg(OH)2 are produced from .319 mol of magnesium nitride? c) How many grams of water are necessary to produce 4.39 mol of ammonia? d) If 12.48g of magnesium hydroxide are

Balancing a number of equations

Balance the following equations: a. S(2)O(3)^2- (aq)+I(3)^- (aq) ->S(4)O(6)^2- (aq) + I^- (aq) b. Mn^2+(aq) + HBiO(3) (s) ->MnO(4)^- (aq) + Bio^+ (aq) (acid) c. Cr(2)O(7)^2- (aq) + H(3)AsO(3) -> H(3)AsO(4) (aq) + Cr^3+ (aq) (acid) d. CIO^1(aq) + Cro(2)^- (aq) ->Cl^- (aq) + CrO(4)^2- (aq) (Basic) e. Obr^- (aq) +HPO(3)^2- (

AP Chemistry

Consider two solutions. One solution is 0.1115 M Ca(OH)(2). The other is 0.1050 M HClO(4). a) Write a balanced equation for the reaction between the two solutions. b) How many mL of Ca(OH)(2) will be required to neutralize 25.00 mL of the HClO(4)? c) If a student starts to titrate 31.39 mL of the Ca(OH)(2) solut

AP Chemistry

Question 3: The salt NaBrO(3) oxides Sn^2+ to SnCl(6)^2- in the presence of hydrochloric acid according to the equation 3 Sn^2+ (aq) + 18 Cl^- (aq)+ BrO(3)^- (aq) + 6 H^+ (aq) -> 3 SnCl(6)^2- (aq) + Br^- (aq) + 3 H(2)O A sample weighing 2.000g is

AP Chemistry Problem

1: Consider mixing solutions of silver nitrate and calcium chloride. a. write a net ionic equation for the formation of the precipitate. b. If 200.0 mL of .300 M silver nitrate are mixed with 350.0 ml of .500 M calcium chloride, how many grams of precipitate are formed? How many moles of each ions are present after orecip

Acidity of various substances

What color- red or blue- would you expect each of the following to produce when added to litmus: Milk of magnesia wine seawater coca-cola tomato juice

Entropy Change of Heating Argon

Calculate the entropy change when 100 g of argon is heated and compressed from 300 K, 1.0 atm, to 900 K, 17 atm, assuming ideal gas behavior. Cp=20.93 J/K mol

Explain solubility rules

Explain solubility rules used to predict precipitation reactions. Predict if precipitation occurs in the mixing reactions of the following aqueous solutions: a) ammonium sulfate + iron(II) nitrate b) potassium iodide + lead(II) nitrate c) sodium nitrate + copper(II) sulfate d) ammonium iodide + silver nitrate

Particle in a Box

Calculate the ground-state energy of a particle in a box of length a, that is subject to a perturbing potential of V(x) = Vx/a .

Understanding volume

If I have the mass total and I'm trying to find the volume of one of the items that makes up the total mass? D=M/V

Helium balloon

If a helium balloon breaks loose it rises into the atmosphere and at some point bursts. Explain why?

Vacuum Question

Materials vacuum chamber and pumper large marshmallow balloon Procedure Wear safety goggles. 1. Place one large marshmallow in the vacuum chamber. 2. Cover the chamber with the dome and insert the pumper into the rubber septum. 3. Raise and lower the pumper slowly and observe what happens to the marshmallow. 4. The

physical chemistry

One problem that we will continue to face as the population of the earth steadily increases is fresh water. Even though there is an abundance of water on this planet, less than 5% of it can be used to sustain life. Therefore, new ways of purifying water are being developed. One of the best recent developments is using reverse

Monoatomic Gas

I need some help deriving the ideal gas equation for a monatomic gas.

Calculating Atomic Fractions Of Fluorine

Calculate the fraction of Fluorine atoms at 1000 K in each of the first three electronic levels based upon the following data: Term symbol..................Wave number (cm^-1).....................Degeneracy P_3/2........................................0.0.................................................4 P_1/2.............