Explore BrainMass

Physical Chemistry

Semi-Empirical Expression for a Dilute Real Solution

Starting with the definition of osmotic pressure Pi = -RT/V_ml * ln * (p_so*ln)/(p_1)^0 Derive the semi-empirical expression for a dilute real solution Pi/C' = RT/M_2 + bC' Where C' is the concentration expressed in (g solute)/(dm3 solution) and b is known as the interaction constant. Then use the semiempirical formu

Calculating Concentration in Equilibrium

At pH 6.00 and pE 2.60, what is the concentration of Fe2+ (mol/L) in equilibrium with Fe(OH)3? Hint: Use the Nernst equation and the Ksp for the solubility of solid iron (III) hydroxide. I would like to know how to set up the Nernst equation and where it is appropriate to plug in the value and how it correlates with the c

Standard Temperature Pressure and Volume

1. The respiratory rate of a person is 20 breathes per minute. If every average breath is about 310cm^3 of air at 22C and 740mmHG, what volume of air in cubic meters and corrected to standard temperature and pressure conditions does a person breathe in one day?

Determination of Molecular SO2 Needed for Protecting Wine

You have just finished fermenting a wine and the pH = 3.7. You need 2mg/L "molecular" SO2 to protect the wine. What level of free SO2 do you have to add to achieve the level of the molecular form desired? You can ignore the sulfite(SO3) form at this pH as the levels will be negligible. Perform by calculation and give answer

Perfect (ideal) gases (4 part question)

Suppose your balloon has a radius of 3 m and that it is a spere when inflated. a.) how much H is needed to inflate it to a pressure of 1 atm at an ambient T of 25 celsius @ sea level? b.) what mass can the balloon lift @sea level, where the density of air is 1.22 kg m^-3 ? c.) what would be the payload if helium were used ins

Calculating Concentration at Equilibrium: Example Questions

The equilibrium constant Kc for the reaction is 54.3 at 430 deg C H2(g)+I2(g) f/r 2HI(g) At the start of the reaction there are 0.714 mole of H2, 0.984 mole of I2, and 0.886 mole of HI in a 1.90 L reaction chamber. Calculate concentrations of the gases at equilibrium: [H2]= [I2]= [HI]=

Calculate equilibrium partial pressure

The heterogeneous equilibrium process C(s) + CO2(g) f/r 2 CO(g) At 700 deg. C. the total pressure in this system is 4.71 atem. The equilibrium constant is 1.52, calculate the equilibrium partial pressures of CO2 and CO. PCO2=? atm PCO=? atm

Concentrations of Components in an Equilibrium Example Questions

The following equilibrium process at 686 deg. C. CO2(g) + H2(g) f/r CO(g) + H20 (g) The equilibrium concentration of the reacting species are [CO]=0.050 M, [H2]=0.045 M, [CO2]=0.086 M, and [H2O]=0.040 M. I calculate Kc for the reaction at 686 deg. C. = 0.52 If CO2 is added to increase concentration ot 0.55 mol/L, what wi

Calculating equilibrium constant with temperature

This is problem having troubles with. Determined at 1123 K. C(s)+Co2(g) >2CO(g) K'p=1.3 x 10^14 < CO(g) + Cl2(g)>COCl2(g) K"p=6.0 x 10^-3 Equilibrium constat expression Kp for reaction C(s) + CO2(g)+2Cl2(g)>2COCl2(g) Kp=(PCOCL2)^2/((PCl2)^2 x (PCO2)) Calculate the equilibrium constant at 1123K

Acid-base titration; density & specific heat of a solid

1.What data is collected in a titration? 2.How would I be able to find what the volume of 0.10M HCl should be needed to titrate .136 g Na2CO3 according to the reaction equation: Na2CO3(aqueous) +2HCl(aqueous) &#61664; 2NaCl(aqueous) + H2O(liquid) + CO2(gas) 3.How would I determine the density of a solid using water di

Molarity and Solubility

1) If ZnCO3 (solid) is insoluble in water, but dissolves in excess 6.0 molar HCl (aqueous), how would pull out the proper equation that would support it? 2) How would you go about finding how many mL of 2.00 molar NaOH (Aqueous) solution are required to neutralize 1.858 g of KHC8H4O4 (it's formula weight being 204.22)? An

Reactions within equations and properties of acidity

A reaction occurs for each of the following below. How do you differentiate between the different driving forces? (a driving force can either be the transfer of electrons; the formation of a precipitate, etc.) 2Na(s) + 2H2O(l) --> 2NaOH(aq) + H2 KOH(aq) + HF(aq) --> KF(aq) + H2O(l) NaF(aq) + HCl(aq) --> NaCl(aq) + HF(

Calculation of Mass

A person ate 0.50 pound of cheese (an energy intake of 4000kJ). Suppose that none of the energy was stored in the body. What mass (in grams) of water would be needed to perspire in order to maintain his original temperature? (It takes 44.0 kJ to vaporize i mol of water).


Calculate the heat of decomposition for this process at constant pressure and 25o: CaCO3(s) ---> CaO(s) + CO2(g)

Chemistry Based Calculations: Molar Solubility

Hi, I need some assistance with the following questions: 1. Calculate the molar solubility of AgCl in a 1.00L solution containing 10.0g of dissolved CaCl2. 2. Compare the molar solubility of Mg(OH)2 in water and in a solution buffered at a pH of 9.0.

Rate Constant with Temperature Changes

Rearrangement of methyl isonitrile to acetonitrile has activation energy of 25.0 kJ/mol and a rate constant of 8.1*10^-4s-1 @ 80 Celsius. what is the value of the rate constant @ 255.0 celsius?

Amount of natural gas burned is proportional

nt of natural gas burned is proportional to the amount of oxygen consumed. if 24.0 kg of oxygen is consumed in burning 15.0 kg of natural gas, how much air, which is 23.2% oxygen by weight, is consumed to burn 50.0 kg of natural gas? a. 80.0 kg b. 345 kg c. 31.3 kg d. 135 kg

Oxidation and reduction - arranging reactions in order

I am having trouble with this question: i) A reacts spontaneously with 1 mol/L BNO3, 1 mol/L D(NO3)2 and dilute sulfuric acid. A does not react with 1 mol/L C(NO3)2 ii) B does not react spontaneously with any of the 1 mol/L solutions above or with dilute sulfuric acid. iii) C reacts spontaneously with dilute sulfuri

Calculating pOH and pH.

Calculate the pOH and pH at 298K of solutions having the following ion concentrations: OH = 1.3 x 10^-2 M.

Calculate Energy Required to Heat Water

Calculate how much energy is required to heat 100 g of ice at 0 degrees Celsius to steam at 100 degrees Celsius. Draw a diagram of temperature versus time for water being heated. Heat of fusion of water = 6.02 kJ/ mole Heat capacity of liquid water = 4.18 J/degree Celsius x g Heat of vaporization of water = 40.7 kJ/ m

Calorimeters and heat capacity

If 2.500 g of Mg is burned in a constant volume calorimeter with a heat capacity of 1.10 kJ/degrees Celsius containing 1.500 L of water at 23.50 degrees Celsius and releases 37.33 kJ of heat, what is the final temperature of the calorimeter and water? Please show your work and solve. Thank you.

Smelters and Galena Conversion

A small smelter converts galena (lead sulfide) into pure lead by heating the ore with an excess of oxygen. Sulfur dioxide is produced as an air pollutant, as a result of the reaction. To remove sulfur dioxide, the flue gas is passed through a slurry of lime (calcium oxide) to produce calcium sulfate. The smelter processes 120

Mass balance

See attached for full problem. The concentration of isobutene in the overhead product is 4.8 mole %, and the concentration of propane in the bottoms is 0.7 mole %. Calculate the moles of the various components in the overhead and bottoms per 100 moles of feed.