Chemistry Questions and Answers May 14, 2020

Circle the strongest nucleophile

NH2 NH2

Provide the product(s) for the E2 elimination below. Draw chair conformations to show how you arrived at your response.

arrived at your response. (5 pts) KOTBU TH,C CI

Provide the products for each molecule illustrated.

H2SO4 CH3 Na 1) 2) H20 8, 1) H. 2) 2. NaOH Br2 H20

Using the IR and NMR spectra provided, determine the molecular structure for C 6 H 12 O 2 . Label any diagnostic peaks on the IR and draw fragments you can determine from the NMR

Integration 9 Integration 9 triplet triplet TMS Integration 5 Integration 7 (reference standard) triplet quartet Integration 6 Sextet (6 peaks)

Using abbreviations (not structures), write the reaction of flavin adenine dinucleotide that gives off energy (AG). Match the items in the left column to the appropriate blanks in the equation on the right. FADH FADH3 H 32H2 FADH3 FAD FADH 2H FADH2 3H H2

Provide a reasonable synthesis for the following molecule from the starting material provided. CN

You need to produce a buffer solution that has a pH of 5.46. You already have a solution that contains 10. mmol (millimoles) of acetic acid. How many millimoles of acetate (the conjugate base of acetic acid) will you need to add to this solution The pKa of acetic acid is 4.74. Express your answer numericaly in millimoles. View Available Hint(s)

How many grams of dry NH4Cl need to be added to 2.00 L of a 0.700 mol L solution of ammonia, NH3, to prepare a buffer solution that has a pH of 9.00 Kb for ammonia is 1.8 x 105. Express your answer to two significant figures and include the appropriate units. View Available Hint(s) A mass of NH4Cl Units Value

A 50.0mL volume of 0.15 mol L HBr is titrated with 0.25 mol L KOH. Calculate the pH after the addition of 20.0 mL of KOH. Express your answer numerically. View Available Hint(s) pH Submit Part C A 75.0mL volume of 0.200 mol L NH3 (Kb 1.8 x 10 ) is titrated with 0.500 mol L HNO3. Calculate the pH after the addition of 25.00 mL of HNO3. Express

For the reaction X(g) 4Y(g) 3Z(g) Kp 3.20 x 10 2 bar 2 at a temperature of 357 C. Calculate the value of Kc. Express your answer numerically.

The ionization constant of a very weak acid, HA, is 3.8 x 108. Calculate the equilibrium concentrations of H3 O, A, and HA in a 0.048 M solution of the acid. 4,0 M A M HA M

Identify the BrnstedLowry acids in the following reactions. (Sec. 2.3) CH3OH HCI CHOH2 III IV II H2 CHOH NaH V VI VII VII a) I III VI, VII b) II, VI c) I. IV. V. VII d) II, III, V, VIII 1. Identify the conjugate acids in the following reactions. (Sec. 2.3) CHNH2 CH3CO2H CHNH3 CH,CO, I II CHOH HCI CHOH2 II IV C,HONa H2 CHOH NaH V VI a) I, IV, VI

What is the stronger acid in the following reaction if the equilibrium constant is much less than 0.01 HNO, HSO4 HO, HSO4 ) b) c) d) 4. Which of the following statements is correct A) The stronger the acid, the weaker its conjugate base. B) The stronger the acid, the stronger its conjugate base. C) The stronger the base, the stronger its conjugate

10. Thymol blue is a pH indicator. It changes colors from red to yellow at pH 1.22.8 and from yellow to blue at pH 8.09.6. Add curved arrows to show the reaction from neutral (yellow) to basic (blue) conditions and the reverse reaction. OH HO OH soco HO HO So, So red yellow blue 11. Draw the conjugate base for each of the following. OH 12. Draw

19. Rank in terms of decreasing acidity OH 20. What is the most acidic group of protons on methyl acetate (This is a flammable liquid with a smell reminiscent of some glues and nail polish.) CH3 H3C 21. From the structures below, what is the strongest acid What is the strongest base HO. HOCF3 22. Heartburn is caused by a buildup of excessive

15. Challenge What is the ratio of protonated HA vs. deprotonated A species for the following compounds at pH 2, 5, 9, and 14 pKa of each is given as 10.0, 10.6, 19.2, 4.87 (L to R) OH OH SH Hint Derive the ratio from henderson hasselbalch equation. 16. Medicinal chemists make slight modifications to molecules in the attempt to increase the

25. Indicate the order of base strength of these compounds by ranking 14 (1 being the strongest base) NCH, O,N NH, NH2 B) NH ON NH3 NH NH NH D) NH NH 67

Ahat is the major frodeuh. Br Navet 7 2)

Vanadium (VI) and an element X forms a compound with the formula VX 3. What would be the formula when this element X combines with a Fe 3+ ion?

What is the effect on the peak corresponding to an acid component when the pH of mobile phase decreases in reverse phase chromatography

7.) What would be the number average molecular weight (ignoring end groups) of the polymer formed (shown below) if the reaction was run to 98 conversion The repeat unit weight is 196 gmol. to

If light is neither reflected nor absorbed by a material, what happens to it Photons do not enter the material at all. Photons are scattered by electrons in the chemical bonds in the material. Photons increase the energy of electrons in the material. Photons pass through the material unchanged. Photons experience total internal reflection and are

Give the systematic (IUPAC) name for the following compounds. Include all stereochemical designations, I.e., cis, trans, E, Z. (R). (S), etc. where appropriate Answer

Q) How many grams of dry NH4Cl need to be added to 2.30 L of a 0.100 M solution of ammonia,NH3, to prepare a buffer solution that has a pH of 9.00? Kb for ammonia is 1.8x 10^-5.

As a technician in a large pharmaceutical research firm, you need to produce 150. mL of 1.00 mol L potassium phosphate buffer solution of pH 7.09. The pKa of H2PO4 is 7.21. You have the following supplies 2.00 L of 1.00 mol L1 KH2PO, stock solution, 1.50 L of 1.00 mol L K2HPO4 stock solution, and a carboy of pure distilled H2O. How much 1.00 mol

The HendersonHasselbalch equation in medicine Carbon dioxide (CO2) and bicarbonate (HCO3) concentrations in the bloodstream are physiologically controlled to keep blood pH constant at a normal value of 7.40. Physicians use the following modified form of the HendersonHasselbalch equation to track changes in blood pH HCO3 pH pK log (0.030) (Pco)

Gastric juice is made up of substances secreted from parietal cells, chief cells, and mucoussecreting cells. The cells secrete HCI, proteolytic enzyme zymogens, mucin, and intrinsic factor. The pH of gastric juice is acidic, between 13. If the pH of gastric juice is 1.1, what is the amount of energy (AG) required for the transport of hydrogen ions

Equilibrium fractionation factors for evaporation of water are aoc 1.0117 and a25c 1.0092. Calculate 8180 of vapor in equilibrium with sea water at (A) 0 C and (B) 25 C.

Do you have any knowledge about recent trends in analytical chemistry? Where I can make a review paper about it.

Above gas is found in a reservoir with 120 F temperature and 3250 psig pressure. What is the ratio of actual gas volume to ideal gas volume at this pressure and temperature MW Mole (Ibmlb mole) Tc (R) Pc (psia) Fraction () H20 N2 H25 CO2 C1 18.015 1164.85 3200.1 1.00 20.010 239.26 507.5 2.36 34.080 44.010 16.043 672.35 1306.0 18.41 164 547.58

Q8. What mass of CaCO, will be precipitated by reacting 36.2 mL of 0.158 M CaCl, with 32.5 mL of 0.149 M Na,CO, The equation for the reaction is CaCl, (aq) Na,Co, (aq) , (s) 2 NaCI (aq)

8. What might the riverine chemistry tell you about its watershed (suspended load and dissolved ions) What assumptions about weathering are built into your understanding

What is the ratio of protonated (HA vs. deprotonated A species for the following compounds at pH 2, 5, 9, and 14 pka of each is given as 10.0, 10.6, 19.2, 4.87 (L to R) SH Hint Derive the ratio from henderson hasselbalch equation.

16. Medicinal chemists make slight modifications to molecules in the attempt to increase the efficacy of the potential drug while also decreasing toxicity and side effects. Lansoprazole (Prevacid) is a protonpump inhibitor that is used in the treatment of ulcers. Would the proton indicated in lansoprazole be more or less acidic than the proton

17. For each set of common laboratory solvents, identify the compound that is more acidic. H,COH H,C CH methanol acetone vs. I HcCI dichloromethane hexane vs. HOH ethyl acetate water vs. ,18. Rank these compounds in terms of increasing acidity HNO, H,SO, HF H,CO3 . NH, CH, H,O HCI b. HO NH, . HO HF OH d.

4. Ascorbic acid is going to be determined by putting a known excess of iodine formed by the action of 10, on KI and backtitrating the remaining lodine with thiosulfate, S,0, 10, 8 H 71 4 1, 4 H,0 Ascorbic Acid 1 dehydroascorbic acid 2 H 21 2 S,0, 1, S,o, 21 Mole vectors aid in visualizing the calculations that are to be performed. Draw

(a The total number of binding sites for the macromolecle B is number) The total number of binding sites for the macromolecule C is (a number) The macromolecule that exhibits the strongest binding to X is (A, B, or C) True or False, macromolecule A binds to X as a monomer F) (T or (T or F) True or False, macromolecule C binds to X as a monomer

Select a mass spectrometric technique with the highest mass resolution for identifying an unknown compound being eluted from a liquid chromatography column

You are performing a titration of an unknown HCl solution. You want to determine the concentration of this unknown. You place 15.0 mL of the unknown in an Erlenmeyer flask. You add one drop of phenolphthalein indicator. You set up a buret with 0.500 M KOH solution. You start adding the KOH to the unknown acid. After adding 41.5 mL of KOH titrant,

1-) A-Name the particles of an atom, and order the particles of atoms a. with respect to their mass and b with respect to the magnitude of their charge B-What is the difference between an atomic number and atomic mass? How many atoms does a 12 gm of carbon atom have? How many grams does 6.02 x 10 23 molecules of water weigh?

Research and find the following information on Periodic Table What is the meaning of a period and family in the periodic table Usually information is present in a box for an element? How does the atomic mass and size are ordered in the table? What kind of elements do yield covalent bonds?

H 10 Li Be B cNO F Ne Metal Metaloid Nonmetal 12 13 14 15 16 17 18 Na Mg Al Si P s cI Ar 20 23 30 31 32 33 34 36 35 K Ca Sc Ti v Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 55 56 5771 72 73 74 75 76 77 78 79 80 82 83 84 85 86 Cs Ba Hf Ta w Re Os Ir

Explain and give examples of different types of chemical bonding? What is a single bond and double bond? Order the strength of single, double and triple covalent bonds from weakest to strongest? What kind of bonds do the aromatic hydrocarbons have? Are they stronger or weaker compared to the bonds of olefin series?

What are main classes of pure hydrocabons? What does alphatic mean? What are the homogous series of the aliphatic hydrocarbons? What is the functional group of these homologous series? How do the members of a homolgous series vary with respect to their functional group? What is the significance of identifying a homolgous series in regard to their

Define and give an example of each of the followings: - Homologous series - Olefin - Diolefin - cyclic hydrocarbon

What are the general formula of the following hydrocarbon series: - Parafin series - Olefin series - Naphthene series - Diolefin series Are they all organic compounds? Which ones are not naturally found in crude oil?

What are the organic hetero-compounds that exists in petroleum ? What kind of problems do they lead to? Research and find the meaning of substituted hydrocarbons? Research find out why oxidation is the most important reaction of covalent bonded compounds (i.e. petroleum as well).

What are the main non-hydrocarbon compounds of petroleum? What kind of problems do they lead in petroleum engineering?

What are the resins and asphaltenes? What are the main physical and chemical differences between them? Are there any problems related to resins and asphaltenes in petroleum engineering practice? Name a few of them.

What are porphyrins? What does it mean if they are present in crude oil

30 lb of methane is held in a sealed container at 100 F. The volume of the container is 2 cu-ft. Calculate the volume of the gas in the container. How do you decide that methane sample in this volume at this temperature is in the gas phase?

25 lb of propane is is held in a sealed container at 350 psi. The volume of the container is 3 cu-ft. Calculate the weights and volumes of the two phases in the container. How do you decide the propane sample is in two phase

ClausiusClapeyron Equation is given as: P vap = vapor pressure H vap = enthalpy of vaporization, J/mol R = 8.3145 J/Kmol T = temperature (in Kelvin ) The vapor pressure of water at 25C is 23.8torr, and the heat of vaporization of water at 25C is 43.9 kJ/mol. Calculate the vapor pressure of water at 65C. Would the result change if you were to use

An ideal gas exerts 100 psig in a cylinder at 100F. What will the pressure be if the temperature is reduced to 32F?

A 20 cu-fttank at 100 F. is pressured with a pure paraffin gas. Then 10 lbs of ethane is added and the specific gravity of the gas mixture is measured to be 1.68. Assuming the gases as ideal gas determine the gas originally fills the tank?

Calculate the mass of methane gas contained at 1500 psi and 88 F in a cylinder with volume of 2.5 cu ft. assume methane is ideal gas, then assume it is non-ideal gas and calculate the error? Repeat the above requirements for ethane gas under the same conditions?

A tank contains methane at 1000 psia and 140 F. Another tank of equal volume contains ethane at 500 psia at 140 F. The two tanks are connected and the gases are allowed to mix and the temperature is restored to 140 F. Calculate the final pressure, the composition of the mixture and partial pressures of the components at final conditions. A. Assume

Calculate the specific gravity and the z-factor for the following gas mixture at pressure of 340 psia and temperature of 200 F: Component Mole Fraction Methane Ethane Propane Aregon 0.850 0.090 0.040 0.020 total = 1.000

In a molten salt reactor, a common type of neutron moderator is lithium fluoride salt that is enriched with lithium7. How many neutron scattering events with lithium7, on average, are needed for a 1.0 MeV neutron to reach an average energy of 2.0 keV Final answer must be the number (n) of total scattering events required rounded to 3 significant

15. What compound will be produced as a result of aniline with nitrite acid interaction A. CHsN N CaH3 B. NH CH4 SONH C. CHsCl D. CHsNNCI E. CHsN NCH4NH2 F. CHsOH.

A chemist adds 0.40 L of a 1.3 x 10 molL silver(II)oxide (AgO) solution to a reaction flask. Calculate the micromoles of silvert) oxide the chemist has added to the flask. Round your answer to 2 significant digits.

2. Sketch the phase diagram for water. Label each phase region (solid, liquid, gas, supercritical fluid), and label the critical point and the triple point.

List all types of Gaussian functions used to describe hydrogen fluoride, HF, in 6-311++G** basis set.

What mass of the following solutions contains 0.100 moles of solute? a. 0.296 m NH 4 NO 3 : _____g b. 1.25 m ethylene glycol (C 2 H 6 O 2 ): ______ g c. 5.19 m CaCl 2 : _____ g

What is the IUPAC name for the following compound

Why salts containing d block metal ions are colored?

A 77.2 g sample of Ag was heated to 58.5 C, and placed in a constant pressure calorimeter containing 100.0 g of water (C, = 4.184 J / g-9 at 24.8 C. If the final temperature of the water was 26.2 C. What is the specific heat capacity of Ag?

11) Predict the product for the reaction below. Dilute HCI in H,0 and acetone 12) Draw the product(s) for the reaction below. KMNO,H,0 pH 7, T 0 C 13) Draw the correct product for the reaction below. Br, (In excess)

14) Draw the correct product for the reaction below. PdCH, 15) Choose the correct product for the reaction below. 1) Li NH2 2) NaCIH,O 16) Write the necessary reagents for the reaction below Reagent HO OH

How to make these compounds?

CN b) CN c) Br OEt

8. Give the IU name for the following comunds. CH3 Cl CH2CH3 CH2CH3 CH3 CH2CH CH3 Cl CH3 H H H H HC H3C H. C. C H. CH3 H CH2CH2CH3 OH CHCH2 H CH2CH2B CH3

Draw the structure of methylphenidate hydrchloride at high ph and at low ph.

OCH, N HCI Methylphenidate Hydrochloride CH,,NO, HCI MW 269.77

why iron oxide there is no reaction between it and conc. acid HNO3 and with HCL there is a reaction in summary

Consider a substance with a heat of solution (AHsin) of 16.7 kJmol. 0.00100 mol of this substance was dissolved in water in a calorimeter to create a solution with a total mass of 8.00 g. If the contents of the calorimeter were initially at 20.0C, what will the final temperature be Assume that the contents of the calorimeter have a specific heat

MATCHING. For these next six questions, match each of the following catalytic proteins with its catalytic activity. Answers may be used more than once, and one answer is not used at all. caspase protease Okinase ATPase GTPase none of these answers t Question 40 Ras protease kinase ATPase OGTPase none of these answers

Q3. Consider the following five point calibration plot using absorbance and concentration. 0.8 0.7 0.6 0.5 0.4 0.3 y 0,4508x 0.0444 R0.9876 0.2 0.1 0.5 1. 1.5 2. Concentration (M) What does slope, intercept and R represent What will be the concentration of an unknown solution if absorbance is o.413 (9 6 15 pts) Absorbance (A)

Why iron differs from the elements before it in the 1st transition series ?

Predict and explain the solubility in water of PROZAC. Based off your knowledge of polar and nonpolar functional groups and the rule of "like dissolves like".

Alkaline batteries use the same chemistry as dry cell batteries except under basic cornditions. True False Question 7 Cadmium, used in nickelcadmium batteries, is an expensive, toxic heavy metal. True False Question 8 E for nickelmetal hydride and nickelcadmium batteries is lower than E for alkaline or dry cell batteries. True False Question 9

Consider a soil with bulk density of 1.43 g/cm 3 soil. Sampling the top 7 inches of this soil and measuring the cation exchange capacity (using the ammonium acetate method) results in the following cations exchanged by NH 4 + : 6.6 cmol Ca 2+ /kg soil, 2.7 cmol Mg 2+ /kg soil, 1.3 cmol K + /kg soil, and 1.3 cmol Al 3+ /kg soil. How much K + is

A parent and daughter nuclides are shown below. What type of nuclear reaction occurred Select all possible types that may have occurred. There may be only one answer or there may be more than one answer. Subatomic particles and other nuclear emissions are not shown. 224 J 116L 16 M 35 36 36 electron capture nuclear fusion beta decay nuclear

What are the expected byproducts of a radical bromination reaction

What is (are) the product(s) that are transferred into the electron transport chain from the citric acid cycle A) NAD and FAD B) NADH, FADH,, and H C) NADH, FADH,, H, and ATP D) ATP E) NAD, FAD, and ATP

Write balanced molecular equations to illustrate each of the following reactions. All the metals form 2 ions. (Use the lowest possible coefficients. Be sure to to specify states such as (ag) or (s). If a box is not needed, leave it blank.) a Magnesium with H2SO, b Zinc with HCI c Calcium with HC,H,O2

Describe with the aid of a diagram a chiral compound and its epimer.

Given the chromatogram shown below, answer the following questions (a) Match the following compounds to peaks shown in the chromatogram, assuming the column is reverse phase benzoic acid, phenol, toluene, benzene, dead peak (i.e. migration time) 5 2 5 6 7 8 Time (min) 3660 Toluene Benzene Phenol Benzoic acid Detector Signal (mAU) 3 9 10

Given the chromatogram shown below, answer the following questions (b) Calculate the adjusted retention time for compoundpeak 3 (in minutes). 20 3. 10 0. 5 8. 10 Time (min) HO OH Benzoic acid Phenol Toluene Benzene Detector Signal (mAU)

(draw all possible structures for the repeat units, and alsc , BCI3 CI 1) 2) excess CI c) (CH2)5CH3 1) CHMgBr Br Br 2) Ni(dppp)2Cl2 HCI (show endgroup structures)

2 Explain the following observations. Set up a balanced reaction equation for the cases where a reaction occurs. 1. Aluminium has a standard reduction potential of 1.66 V for the half cell reaction Al 3e Al. However, it does not spontaneously combust at 298 K in ambient atmosphere. Why 2. Aluminium dissolves in dilute sulfuric acid. 3. Aluminium

Why iron has not the oxidation state corresponding to the removal of all electrons (4s and 3d) Is it differs from the remaining 1st transition elements?

D. Based on the following coupling constants, approximate the signal for Hg. Use Pascals Triangle to get the height ratios. Each line is 2Hz. The center peaks are started for you. E. What is the predicted peak shape of proton Hg Ph E A. Ph JAB 6 Hz JBC 6 Hz 3D 3D Br Br A

Give reactions to make this product

Ph Ph

Convert the following LP to the Karmarkars LP and perform one iteration of Karmarkars method for it. Max z= 3X1+X2 Subject To 2X1-X2 2 X1+2 X2 5 X1,X2 0

8) Draw the skeletal structure 3(diethylamino)cyclopentan1ol. Draw all the possible stereoisomers for the structure drawn above. Label each asymmetric center and explain the relationship between each stereoisomer. B A D Explanation

Draw what would happen to 2,5-dimethyl-2-hexene in alkyl halides and alkane reaction. This is for a concept map. So what would the alkene 2,5-dimethyl-2-hexene be as an alkyl halide and how to you go from an alkene to an alkane with 2,5-dimethyl-2-hexene. No bond lines. I know this much for alkene to alkane

CH3 CH3 H2Pb CH CH CH CH alkane hydrogenation CH3

Compound A is expected to show optical activity. True or False Br A C

The following synthesis requires more than onestep. How would you carry out the conversion

Which is the major organic product from the following reaction OH 1. Br2, PBr3 OH 2. H0 HO Br OBr HO Br

3.) For each of the following structures, star any chiral centers and label each chiral center as (R) or (S). a. COH HO... CH H CHSH b. HC H CH Br NH CH OH