How do you read infrared spectrometry graphs and determine the types of bonds that are shown at each peak? Also, how would you read a graph and determine which compound is being shown?

Suppose 3 large tankers containing liquefied natural gas (LNG) leave a gas export terminal every day. The methane is stored in liquid form in the tankers, at -260°F, in a volume 600 times smaller than would be needed in gas form, at STP (Standard Temperature and Pressure: 0°C temperature, 1 atm pressure). Suppose the average tanker at this port carries an amount of LNG equivalent to 125 million cubic meters of methane at STP. The energy content of methane is 38.5 MJ per cubic meter at STP. How many gigawatts (GW) of power does this daily flow of natural gas through the port represent?

Sorbose, C6H12O6, is a carbohydrate used in the manufacture of vitamin C. A lab supervisor at Vital C Pharmaceuticals, Inc. suspected that an employee had sabotaged the production line by substituting xylitol, C5H12O5, a sweetener for "sugar-free" gum, for sorbose. Combustion analysis of the white powder found in the production line and in the employee's possession gave the following results: %C = 39.47; %H = 7.95; %O = 52.58 Was the employee guilty of sabotage and thus should the employee be fired for sabotage?

Consider the titration of a 26.0-mL sample of 0.175 M CH3NH2 with 0.155 M HBr. (The value of Kb for CH3NH2 is 4.4×10−4.)

A. Determine the initial pH.

B. Determine the pH at 6.0 mL of added acid.

C. Determine the pH at one-half of the equivalence point.

D. Determine the pH after adding 4.0 mL of acid beyond the equivalence point.

Which of the following will increase the number of theoretical plates in a chromatographic separation? Select all that are appropriate.

	decrease column packing particle size
	increase column mobile phase flow rate
	increase column length
	change mobile phase to one with a greater analyte diffusion coefficent

1. After glycogen reserves are depleted what are the major gluconeogenic precursors of glucose under the conditions of

A. starvation

B. intense exercise

Calculate the pH change when 5.0 mL of 5.0-M NaOH is added to 0.500 L of a solution of:

(The pKa for acetic acid is 4.74.)

a) 0.50-M acetic acid and 0.50-M sodium acetate.

pH change = _____

b) 0.050-M acetic acid and 0.050-M sodium acetate.

pH change = ______

c) 0.0050-M acetic acid and 0.0050-M sodium acetate.

pH change = _______

A mixture if Krypton and Neon gases, at a total pressure of 678mm Hg, contains 5.96 grams of krypton and 4.42 grams of neon what is the partial pressure of each gas in the mixture in mm Hg?

Three flasks, labeled A, B, and C, contained aqueous solutions of the same pH. It was known that one of the solutions was 1.0 × 10–3 M in nitric acid, one was 6 × 10–3 M in formic acid, and one was 4 × 10–2 M in the salt formed by the weak organic base aniline with hydrochloric acid (C6H5NH3Cl). (Formic acid is monoprotic.)

(a) Describe a procedure for identifying the solutions.

(b) Compare qualitatively (on the basis of the preceding information) the strengths of nitric and formic acids with each other and with the acid strength of the anilinium ion,

(c) Show how the information given may be used to derive values for Ka for formic acid and Kb for aniline. Derive these values.

The Common-Ion Effect and pH Buffers

1. Calculate the pH at 25°C of 1.00 L of a buffer that is 0.120 M HNO₂ and 0.150 M NaNO₂ before and after the addition of 1.00 mL of 12.0 M HCl.

pH Indicators and Acid–Base Titrations

2. A 25.0 mL sample of 0.100 M acetic acid is titrated with 0.125 M NaOH. Calculate the pH at 25°C of the titration mixture after 10.0, 20.0, and 30.0 mL of the base have been added.

Solubility Equilibria

3. pH of Milk of Magnesia What is the pH at 25°C of a saturated solution of magnesium hydroxide (the active ingredient in the antacid milk of magnesia)?

A 0.450 gram sample of impure CaCO3 (s) is dissolved in 50.0 mL of 0.150 M HCl (aq). The equation for the reaction is CaCO3(s) + 2HCl --> CaCL2 (aq) + H2O (l) + CO2 (g). The excess HCl (aq) is titrated by 7.20 mL of 0.125 M NaOH (aq). Calculate the mass percentage of CaCO3 (s) in the sample.

1. Graduated cylinders are not as precisely calibrated as are burets or volumetric pipets. Briefly explain why it is acceptable to measure the KI and HCI solutions used in the titration with graduated cylinders rather than with pipets or burets. 2. Would the following procedural errors result in an incorrectly high or low calculated precent NaOCI in commercial bleaching solution? Briefly explain. (1) A student failed to allow the volumetric pipet to drain completely when transferring the diluted bleaching solution to the Erlenmeyer flask. (2) A student blew the last drops of solution from the pipet into the volumetric flask when transfeering commercial bleaching solution to the flask. (3) A student began a titration with an air bubble in the buret tip. Thhe bubbl came out of the tip after 5 mL of Na2S2O3 solution had been released.

Why is Vmax not a constant? Why do we want to analyze kcat instead of Vmax?

A. While both NaBH4 and LiAlH4 can both be used to reduce ketones and aldehydes, the procedure that you followed in lab would not result in the fluorenol product if NaBH4 were simply replaced with LiAlH4.

i) Explain why.

ii) What change to the procedure would have to be made to use LiAlH4 tosuccessfully reduce fluorenone to fluorenol?

B. NaBH4 is not capable of reducing esters since estersare less reactive than ketones. Explain structurally why this is the case.

C. In a lab, NaBH4 is kept in a dessicator to avoid prolonged contact with water in the atmosphere. This is done since waterwill react with NaBH4. Write the balanced equation for the decomposition of NaBH4 by water.

D. It is found that a bottle of NaBH4 in a lab contains 70% NaBH4 by mass as a significant portion has reacted with atmospheric water as described in question 3 above. What is the minimum that a student should weigh out to fully reduce 3.18 g of fluorenone?