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Physical Chemistry

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 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

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?

Solvent: Finding the Kf Value

Question: A solution of 0.2113 g of water dissolves in 25.0 g of a solvent which freezes at 11.5 EC below the freezing point for the pure solvent. What is the Kf value for this solvent?

Calculate temperature using vapor pressure

Hi, Please explain the math as elementary as possible. Thanks. The vapor pressure of Ethanol is 115 torr at 34.9EC If H sub vap = 40.5 kJ/mol, calculate the temperature (in EC) at which the vapor pressure is 760 torr.

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)

Solution Concentrations

Find the concentration of 500mg of alltrans retinol 0.1% per 1 ounce of solution. Vitamin A C20H30O F.W. 286.46 CAS 68-26-8 Ratings Health: 1 Flammability: 1 Reactivity: 0 Chemical Specifications: Assay Min. 99% Storage Information: LIGHT SENSITIVE, REFRIGERATE: Keep tightly clos

Heating and Cooling Chemical Reactions

Why when heating and cooling three different separate substances in open containers does the mass change in two of them (one loss mass; the other gained mass) but stays the same in the third when it is known that mass is conserved in chemical reactions? Would it be because one gave off vapor, the second melted and the third was

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

Fugacity from Bethelot equation

Carbon dioxide obeys the reduced Bethelot equation reasonably well (i have attached the equation) Given Tc = 304.3K and Pc = 73.0 atm, calculate the fugacity of carbon dioxide at 150 degrees C and 50 atm.

Ideal gas law? free energy of mixing ...

I think the ideal gas law does not apply in this following problem because this problem is addressing a liquid. then how do i think through and do this problem? Calculate the free energy of mixing when 1 mole of liquid A is mixed with 4 moles of liquid B at 25 degrees C to form an ideal solution. What is the change in chemic

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?

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 Kc

Given the amount of reactant in grams in a container at a temperature and amount produced in moles, calculate Kc: A quantity of 6.75 g of SO2Cl2 place in a 2.00 L flask. At 648 K, there is 0.0345 mol of SO2 present. Calculate Kc for the reaction. SO2Cl2(g) f/r SO2(g)+Cl(g)

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)  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(

Thermodynamics Question

I solved part a of this problem easily. The rest of this problem has me stumped. I already have the solutions to these problems, but it's arriving at these solutions that has made me pull my hair out!

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.

Electrolyte Concentration and Polarization Potential

I am having some trouble with this question. Question: a) A copper refining cell is operating with an electrolyte which contains 0.05 m Sn2+. At what concentration of Cu2+ will the tin start to plate out in preference to the copper? The cell temperature is 40 degrees Celsius. b) A polarization potential arises from a con

Solubility Constant, Ksp of Reactant

The chemical reaction representing the soluability of AGBr is: AgBr (right and left arrow) Ag^+ +Br^- This can be written as: AgBr+ 1e^- (right arrow) Ag + Br^- Eo=.071 V Ag (right arrow) Ag^+ +1e^- Eo=-.800 Using this data, what is the solubility product constant, Ksp, of AgBr @ 25 Celsius?

Calculating cell potential...

Calculate the cell potential @ T=25 celsius assuming ideal solutions Fe | Fe^2+ (1.43 *10^-5) || Fe^2+ (5.00*10^-4M) | Fe The double line represents a salt bridge. I need detailed description of what they are talking about here - I haven't a clue!!