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# Physical Chemistry

### 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

### 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

### Calculating molar concentrations of acetic acid

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

### Ferrous ion reaction

How do I calculate the moles of iron (ore sample) and how do I calculate the mass percent of iron in the ore from this problem; Ferrous ion reacts with permanganate ion Mno4 in acidic solution to produce the ferric ion Fe3. A 6.893 gram sample of ore was mechanically crushed and then treated with HCl which oxidized all the ir

### Solve: Molarity and Molality

Question: Ethylene glycol, C2H6O2 (MW=62.1mol) has a density of 40.0 mass percentage and a solution of ethylene glycol in water is 1.0514 g/mL at 20 EC. Calculate the molality of the solution. Calculate the molarity of the solution.

### Calculating vapor pressure using temperature

Hi, Please explain as ELEMENTARY as possible. Thank you (-: A liquid has a heat of vaporization of 35.5kJ/mol and a boiling point of 122 EC at 1 atm. What is its vapor pressure at 109EC?

### Solve: Molarity

Please help with understanding the math for the following question: Question: A solution is prepared by dissolving 17.75 g of sulfuric acid (H2S04;MW = 98.0 g/mol) in 93.2 g of water. If the density of the solution is 1.1094 g/mL, what is the molarity of the sulfuric acid?

### Understanding Vapour Pressure

Which would you expect to exhibit the highest vapor pressure at room temperature? - Helium(Delta H fusion 0.02, Delta H vaporization 0.10) - Benzene(Delta H fusion 9.95, Delta H vaporization 30.8) - Water(Delta H fusion 6.01, Delta H vaporization 40.67) - Mercury(Delta H fusion 2.33, Delta H vaporization 56.9).

### Gibbs-Duhem Equation

In a certain binary solution, the activity of component 1 is given by R * ln(alpha_1) = R * ln(x_1) + A(x_2)^2 + B(x_2)^3 Where x_1 and x_2 are the respective mole fractions and A and B are constants. Derive an expression for alpha_2 (the activity of component 2) given that the equation above is valid over the entire conc

### 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

What is the theoretical yield of vanadium that can be produced by the reaction of 40.0 g of V2O5 with 40.0 g of calcium based on the following chemical reaction. V2O5(s) + 5Ca(l) --> 2V(l) + 5CaO(s)

### Energy of Visible Photos and Breaking of the Bond in AgI

The silver iodine bond energy is approx 255kJ/mol. (AgI is one of the active components in photography sunglasses). What is the longest wavelength of light capable of breaking the bond in silver iodine?

### 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

### Finding Kc from Products' Moles, Volume and Percent Reacted

The following reaction occurs at 1600 deg. C. Br2(g) <---> 2Br(g) When 1.05 moles of Br2 are put in a 0.980 L flask, 1.20 percent of the Br2 undergoes dissociation. Calculate the equilibrium constant Kc for the reaction.

### Calculate Kp given total pressure

NH4Cl(s) f/r NH3(g)+HCl(g) Calculate equilibrium constant Kp if the total pressure is 2.9 atm at this temperature.

### 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).

### Calculation

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.