A 15.2% (m/v) solution of sodium chloride (NaCl) is used to prepare 25.0 L of a physiological saline solution with a concentration of 0.154 M NaCl. What volume of the 15.2% (m/V) solution of sodium chloride would be required to make 25.0 L of the physiological saline solution ( 0.154 M NaCl) ?

1) Calculate the maximum wavelength of radiation (corresponding to the minimum energy) necessary to eject a 1s electron from a 27Al atom (which has a 1s1s binding energy of 1559.6 eVeV).

The average kinetic energy of the molecules in a gas sample depends only on the temperature, T. But given the same kinetic energies, a lighter molecule will move faster than a heavier molecule. What is the rms speed of Cl2 molecules at 347 K? What is the rms speed of He atoms at 347 K?

Elemental S reacts with O2 to form SO3 according to the reaction:

2S+ 3O2--> 2SO3

a.) How many molecules are needed to react with 5.74g of S? Express your answer numerically in units of molecules.

b.) What is the theoretical yield of SO3 produced by 5.74 g of S? Express your answer numerically in grams.

Next, consider a situation in which all of the S is consumed before all of the O2 reacts, or one in which you have excess S because all of the O2 has been used up.

c.) For each of the given situations, indicate whether S or O2 is the limiting reactant. Drag each item to the appropriate bin.

Bins: Limiting reactant is sulfur, and Limiting reactant is oxygen

Choices:

   - 3.0 mol sulfur, 4.0 mol of oxygen

   - 3.0 mol sulfur, 3.0 mol oxygen

   -3.0 mol sulfur, 5.0 mol oxygen

Consider the following reversible Hetererogenes reaction:

C(s) + CO2(g) -><- 2CO(g)

When equalibrium is reached at a certain point the total pressure of the system is found to be 4.98 atm. If the equilibrium constant Kp for this reaction is equal to 1.67 at this temperature, calculate the equilibrium partial pressures of CO2 and CO gases?

P(CO)eq= ?      P(CO2)eq=?

Discuss the physical appearance of the aqueous tea solution versus the o¬rganic solution; why is tea so dark?

1.) A can of soft drink consists of CO2 dissolved in water and a vapor space filled with CO2 and H2O vapor. Your goal is to find the mole fraction of CO2 in the liquid mixture at 2 bar and 17 C.

a.) Write down the equation that describes the vapor-liquid equilibria for water-vapor in this system and name the variables involved

b.) Write down the equation that describes the vapor-liquid equilibria for CO2 in this system and name the variables involved

c.) What is the Psat of water-vapor at these conditions?

d.) If the Henry’s constant for CO2 at this temperature is 1280 bars, what is the mole fraction of CO2 in the liquid mixture?

e.) What is the Antoine’s equation? What happens to the Psat of a substance as the temperature increases? Explain the behavior in your own words.

Show work please

1. 3 Sn2+(aq) + 2 Al(s)??2 Al3+(aq) + 3 Sn(s). What is the voltage for this cell?

2. What is the Gibbs Free Energy for the above reaction assuming standard conditions?

3. What is the Gibbs Free Energy for the cell in question 1 if the Sn2+(aq) is [.15] and Al3+(aq) is [1.80]?

4. Describe what happens within the salt bridge between the two cells

Analytical Chemistry - Determination of Fe in Vitamin tablet:

Iron was reduced by 25 mL 6M HCl and DI water.

Unknown Iron Sample: 10 mL diluted with DI water in 100 mL volumetric flask,

Iron Standards: 30 mL of 0.7385 mM

2 mL of hydroquinone solution, 3 mL o-phenanthroline solution and 10 mL of pH 3.5 buffer added to all flasks.

All flasks were diluted to the 100 mL mark. Spectroscopy was used to measure the absorbance at 510 nm and values of wavelength and absorbance for 6 runs are known.

Please explain in detail how to plot a Beer-lambert law from my wavelength and absorbance data in excel. How to plot the absorbance vs. iron concentration added in the standards (in μg) and calculate the μg of iron in the standards and determine the unknown concentration from the curve?

There are 1000 P₄ molecules and 500 S₈ molecules in a container. These are made to react and form P₂S₅ molecules. How many molecules of the excess reactant would remain unreacted in the reaction vessel? Use factor label method for your calculations.

Select one:

a. 800

b. 2400

c. 600

d. 1200

Which one of these molecules contains the least amount of energy: CMP, CDP, or CTP? Explain why.

Below is the data for three titrations. In this experiment we have 25 mL (approx. 0.03M) of various monoprotic acids and we slowly add 50 mL of NaOH while monitoring pH. We add NaOH to change pH about 0.15 after each addition. We add unti lthe total 50 mL of base solution (NaOH) is added. Knowing this, for each trial, what is the equivalence point(s) and the pK_a

In a constant-pressure calorimeter, 65.0 mL of 0.340 M Ba(OH)2 was added to 65.0 mL of 0.680 M HCl. The reaction caused the temperature of the solution to rise from 21.83 �C to 26.46 �C. If the solution has the same density and specific heat as water, what is ?H for this reaction (per mole of H2O produced)? Assume that the total volume is the sum of the individual volumes.

If a student accidentally ran their TLC plate with 30% hexane/ether (instead of the 30% ether/hexane as directed), briefly explain who their TLC results would differ.