Explore BrainMass

Physical Chemistry

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 %?

Free Energy Change of a Reaction

Consider the combustion reaction for propane below. CH3CH2CH3(g)+5O2(g)-------->3 C02(g)+4H20(g) a) Determine the delta G standard state at 298 K from the following standard state values at T= 298 S(CH3CH2CH3)=269.9 J/K mol S(C02)= 213.7 J/K mol S(H20)=188.8 J/K mol S(02)=205.1 J/ K mol delta H(CH3CH2CH3)=-103.9 kJ/mol

Relationship of Enthalpy with P and T

Show that the partial of H with respect to P at constant T =0 for an ideal gas. Hint: start with dH=VdP+TdS. Divide by dP and impose constant T. Use a maxwell relation from dG.

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.

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

Mass of Material

Calculate the mass of material required if 1000 calories of energy causes a change from -27ºF to 91ºC and the specific heat capacity is 0.25 joules/gram-degree C. The distance planet Inverse has a unique temperature scale. Their degree is not equivalent of our Celsius degree; they measure the freezing point of water as 100

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- (

Titration Chemistry Problems

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 Calculations

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

Dissolution of monoprotic acid

A 0.1mol/L aqueous solution of weak monoprotic acid (contains one ionizable hydrogen atom) has a hydrogen ion concentration of 0.001mol/L. The value of the ionization, Ka, for this acid is: a) 10^-5 (10 to the power of -5) b) 10^-2 (10 to the power of -2)

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.

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

Standard Enthalpies of Reaction

50 g of C16H34 are burned with insufficient oxygen for complete combustion to CO2. C16H34(s) + 16.5 O2(g) -> 16 CO(g) + 17 H2O(l) and some of the reaction forms CO2 and H2O(l) in the reaction C16H34(s) + 24.5 O2(g) -> 19CO2(g) + 17H2O(l) (P=1 bar, T=298.15K, heat change = -1945.2 kJ) 1. Compute percent C16H34 that reacted

Monoatomic Gas

Please provide 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.............

Working with Ideal Gas Law

The pressure of a sample of gas at a constant temperature of 25 degrees C is increased from 1.0atm to 1.3atm. If the original volume was 3.8 liters, what will the new volume (in liters) be?

Various Basic Chemistry Problems - Mole, Mass and other Calculations

1) When a mole of C2H4 is combusted it reacts with 3 moles of O2 to produce CO2 and H2O. How many moles of CO2 and how many moles of H2O are produced? 2) What is the mass in grams of 4.25 moles of Mg (NO3)2? 3) The overall reaction producing iron from an ore in a blast furnace is: Fe2O3 + 3CO --> 2Fe + 3CO2 How many

Calculating Ion Concentration and pH

1) Calculate the hydrogen ion concentration and the pH of the solution formed when 0.020 gram-formula weight of nitric acid is added to one liter of aqueous 0.20 M ammonia solution. Assume no significant volume change upon addition of the acid. 2) Calculate the molar concentration of acetic acid at equilibrium in an acetic ac