The average human body contains 5.10 L of blood with a Fe2+ concentration of 3.20×10−5 M . If a person ingests 11.0 mL of 25.0 mM NaCN, what percentage of iron(II) in the blood would be sequestered by the cyanide ion?

Copper(I) chloride has K_sp = 1.7 × 10^-7. Calculate the molar solubility of copper(I) chloride in pure water and in various aqueous solutions.

a. Calculate the molar solubility of CuCl in pure water. b. Calculate the molar solubility of CuCl in 0.0200 M HCl solution. c. Calculate the molar solubility of CuCl in 0.200 M HCl solution. d. Calculate the molar solubility of CuCl in 0.300 M CaCl₂ solution

For the reactions shown below, we added 2.25 mL of 0.0460 M HCl to a test tube containing one of the two cations (Ag⁺ or Pb²⁺) and recovered 0.0148 g of precipitate.

AgNO₃(aq) + HCl(aq) → AgCl(s) + HNO₃(aq)
Pb(NO₃)₂(aq) + 2 HCl(aq) → PbCl₂(s) + 2 HNO₃(aq)

How much precipitate in moles would be recovered theoretically if the ion was Ag⁺? (Enter an unrounded value. Use at least one more digit than given.)


How much precipitate in moles would be recovered theoretically if the ion was Pb²⁺? (Enter an unrounded value. Use at least one more digit than given.)
mol

How much precipitate in grams would be recovered theoretically if the ion was Ag⁺?


How much precipitate in grams would be recovered theoretically if the ion was Pb²⁺?

Select the answer for which all statement(s) is/are TRUE regarding ligands in coordination complexes:

I. Complexes with CN = 4 are typically square planar for d^8 metal centers.

II. Chelating ligands always bind the metal center in a polydentate fashion (CN ≥ 2).

III. The charge of the ligands is the only component needed to determine the metal oxidation state in a complex.

IV. Optical isomers exist when a molecule can be superimposed upon its mirror image.

Answer choices:

A) I, II, and IV

B) II only

C) I and II

D) I and III

A weak acid HA (pKa = 5.00) was titrated with 1.10 M KOH. The acid solution had a volume of 100.0 mL and a molarity of 0.107 M. Find the pH at the following volumes of base added: Vb = 0.00, 1.00, 5.00, 9.00, 9.90, 10.00, 10.10, and 12.00 mL. (Assume Kw = 1.01 ✕ 10−14.)

Given a circular sheet of paper with a weight of 0.15 ounces and a diameter of 4.7 in. Calculate the basis weight in terms of g/m^2. Assuming the circle was cut from a piece of copy paper, what would be the basis weight of the paper in lb/ream?

Consider the following reaction: A(g)⇌B(g)+C(g) Find the equilibrium concentrations of A, B, and C for each of the following different values of Kc. Assume that the initial concentration of A in each case is 1.0 M and that the reaction mixture initially contains no products. Make any appropriate simplifying assumptions.

Part A: Kc= 1.0 Express your answer using two significant figures. Enter your answers numerically separated by commas.

Part B: Kc= 2.0×10⁻² Express your answer using two significant figures. Enter your answers numerically separated by commas.

Part C: Kc= 1.4×10⁻⁵ Express your answer using two significant figures. Enter your answers numerically separated by commas.

33. A certain zero order reaction has a half live of 2.5 seconds when the initial concentration is 2.5 M. What concentration of the reactant remains after 4.5 seconds?

34. The reaction shown below obeys second order kinetics with k = 2.50 x 10-3 M-1s-1 at 25 oC. If the initial concentration of A is 2.00 M, how long will it take for concentration of A to decrease to 35.0 % of its original value?

    A + A → products

35. For a certain second order reaction, k = 0.075 M‒1s‒1. If 0.0025 M of reactant remains after 15 minutes, how much of the reactant was present initially?

36. A certain reaction is known to be second order in [A]. What is the numerical value of k, the specific rate constant, if the concentration of [A] decreases from 1.50 M to 0.25 M after 225 seconds?

37. A certain reaction is known to be second order in A with k = 0.95 M‒1s‒1. What is the numerical value of the half-life (τ1⁄2) when the initial concentration of A is 0.45 M?

Calculate the number of pounds of CO 2 released into the atmosphere when a 21.0 gallon tank of gasoline is burned in an automobile engine. Assume that gasoline is primarily octane, C 8 H 18 , and that the density of gasoline is 0.692 g ⋅ mL − 1 . This assumption ignores additives. Also, assume complete combustion. Useful conversion factors: 1 gallon = 3.785 L 1 kg = 2.204 lb

When calcium carbonate is added to hydrochloric acid, calcium chloride, carbon dioxide, and water are produced.

CaCO3 + 2HCl ----------> CaCl2 + H2O + CO2

A) How many grams of calcium chloride will be produced when 32g of calcium carbonate are combined whith 12.0g of hydrochloric acid?

Mass of CaCl2:

B) Which reactant is in excess and how many grams of this reactant will remain after the reaction is complete?

Mass of excess reactant:

Distinguish between the following adsorption isotherms: Langmuir, BET, Temkin and Freundlich. Indicate when and why each is likely to be appropriate.

The reaction 2H2S(g)⇌2H2(g)+S2(g) Kc=1.67×10⁻⁷ at 800∘C is carried out with the following initial concentrations: [H2S] = 0.150 M , [H2] =0.375 M , and [S2] = 0.00 M. Find the equilibrium concentration of  [S2].

Procedure:

1. A 25 mL round bottom flask equipped with a stir bar is loaded with 13 mg of CdO powder, 0.6 mL of oleic acid, and 10 mL of 1-octadecene. The reaction flask is placed into a heating mantle and surrounded with aluminum foil so that the temperature can reach 225 °C, which will take approximately 1 hr. Some hot plates may heat up faster and the experiment can be performed sooner.

2. As the CdO solution is heating, the Se solution should be prepared. Five students can share the Se solution, since only 1 mL is required for each reaction. A 25 mL round-bottom flask equipped with a stir bar is loaded with 30 mg of Se and 5 mL of 1-octadecene and allowed to stir at room temperature. To this stirred solution was added 0.4 mL of trioctylphosphine via syringe. The mixture will turn homogeneous. At this point it is ready for the next step.

3. Once the CdO solution has reached a temperature of about 225 °C, add 1 mL of the Se solution from step 2 in a rapid fashion. As soon as you add the Se solution start collecting samples of approximately 1 mL into separate test tubes continuously as the reaction will be changing colors from yellow to orange to blood red.

4. After allowing the quantum dot solutions to cool, add 1 mL of pentane to the test tube containing ~1 mL of sample. Then, pipette the samples into a glass cuvette to record their UV-Vis spectra. Use pentane as the blank. The solutions collected in test tubes can be stored overnight in the hood or drawer without decomposition if there is not enough time to record UV-vis spectra.

What reaction is occurring when the selenium dissolves after trioctylphosphine is added?

Write short notes on:

1. Preparation of elements by chemical and electrochemical routes.
2. Variable oxidation states in oxides and oxoanions of main group elements. ( chloride or nitrogen or
3. Use of metal complexes as anticancer agents.
4. Different structures and functions in some copper proteins.
5. The design and mechanism of the dye-sensitized solar cell.
6. Electrochemical synthesis of the elements.
7. Harnessing energy in natural and artificial photosynthesis.
8. Use of electrolysis in preparation of the elements.