Chemistry Questions and Answers June 13, 2020

A container has 3.82g C6H140) in it. There is 13.9L of space in the container and it is at a constant 25C. If 40.1psi of O2 gas are added and react with the CH140 to make CO2(e) and H2O find the pressure in PSI after reacting. Assume no vapor pressure. Assume liqud volume doesnt affect gas volume.

Identify the chiral centers of the following anti-biotic molecule and name the chiral as R or S. Provide the Fischer projection of R, R isomer.

NO HCNHCo CH,OH CHCI,

(a) Draw acetylcholine. See b before you start. (Note that you must include a short narrative that describes waht occurs mechanistically.) (b) What atom on what amino acid in the esterase site of acetylcholine esterase reacts with the substrate? Include a cartoon depiction of the enzyme surface (drawn under and surrounding your acetylcholine

Write the oxidation halfreaction, reduction halfreaction, and the net redox reaction between KMNO4 and FeCl,. Explain why the oxidation capability of permanganate increases in acidic medium. What happens when basic medium is used instead A 0.1298g sample of KBrO3 was dissolved in dilute HCl and treated with an unmeasured excess of KI. The

Complete the Table. From the data, determine the total acidity in terms of % H2C2O3.2H2O. (15 points) 1 ml HCl = 0.9690 ml NaOH TRIAL 1 TRIAL 2 Weight of sample, g 1.018 1.027 Final reading: NaOH, ml 18.78 36.89 Initial reading: NaOH, ml 0 17.87 Final reading: HCl, ml 0 0.27 Initial reading: HCl, ml 0 0 Value of HCl, in terms of NaOH Net volume of

Discuss the mechanism of how poly(p-phenylene) gets metallic conductivity after doping. Draw three band structures to illustrate it from undoped, partially doped, and sufficiently doped. An example of band structure was given.

vacuum energy EA LUMO IP band gap HOMO 23 Energy

For a particular application in my lab, we often need to make a benzoic acid buffer. The chemical formula for benzoic acid is HCHCO. To make this buffer, lets say we start with 1.53 M sodium benzoate in 1 L of water (and assume 11 of volume throughout this problem). 1. (4 pts) Using the chemical formula information above, show the chemical

Draw the prospected product from the following reaction scheme, please denote the intermediates of each step. Please include charge on these intermediates.

H3C H. 1.NaH 2. Molecule 2 3. MORE BASE Molecule 2 H3C CH3

Do the ICE tables.

Part B Data Table Beaker FeJinitial SCN Jinitial Absorption FESCN2 leg Exp 1 1.00x 103 Exp 2 0.04 4.08x10 100x103 b00x 404 0.14 4.66x105 Exp 3 1.00 x 10 4.00x 104 0.29 8.92x105 Exp 4 1.00x 103 6.00x 104 0.49 1.46x104 Exp 5 1.00x10 8.00X 104 0.69 2.03x104 Exp 6 1.00x 103 1.00x103. 4.03x104 0.34 Lime of buit gr equstion y 3526 x 0.0244

2 C6H10 + 17 O2 12 CO2 + 10 H2O If I do this reaction with 35 grams of C6H10 and 45 grams of oxygen, how many grams of carbon dioxide will be formed?

Find the unknown compound, the information posted is the only info given. the melting point range is between 140-146.8 degrees, the substance is soluble in water and soluble in NaHCO3

HNMR 14 12 10 Ppm CNMR 200 180 160 140 120 100 80 60 40 20 ppm Fo

27.16 ml of a solution of the acid H,SO, is titrated, and 88.00 ml. of 0.5400M NaOH is required to reach the equivalence point. Calculate the onginal concentration of the acid solution 0.02376 X M Resubmit Shew Approach Show Tutsteps

Explain how your average experimental enthalpies can be used along with the known heat of formation of water to determine the heat of formation of MgO using Hesss Law. ,questionl TrialtMao SOMLY4.184x3,8794,96o000.79496 O.100759 imor 0.0025 mel 0.79496317.98Kjlmal 0.0025 Tral2Mac SOX 4.18484.5941.410003D0.9414k ol02x 30 0.00253 0.9414 O.00253

3. Propose a synthetic scheme to create the following product. Clearly denote each intermediate and the conditions that are used to generate them. (25 points total) a. (5 points) OH CH, CH3 H,0 CH, H,C Just in case you cannot see the ketone reagent

You perform an alkalinity test on a water sample with an initial pH of 9.75. The alkalinity is 12.1 mg/L as CaCO3. (a) Calculate the CT value. 1.5410-4 M (b) Determine whether there is any potential to precipitate CaCO3 in the pipes given a calcium concentration of 15 mg/L. Justify. Calculations show that it exceeds the Ksp, so yes there is a

Explain how each interatomic interaction you show is involved in the catalytic mechanism. Use 3-letter amino acid nomenclature you assigned in your drawing as part of your explanation. What type of chemical reaction mechanism or phenomenon occurs in each instance?

What are the concentrations of K), OH, CO32 and (H), in a 1.2 M solution of K2CO3 (Note Question is asking for concentrations and not pH) Acid Name Formula Ka1 Ka2 Carbonic H2CO3 4.3 x 107 5.6 x 1011 a. 1.2 M, 8.19 x 106 M,1.19 M, 1.2 M Ob. 1.2 M, 0.015 M, 1.19 M, 1.2 x 109 M Oc. C. 2.4 M, 0.015 M, 1.19 M, 6.67 x 1013 M Od. 2.4 M, 8.19 x 10 6 M,

6. You are studying an enzyme, USFase, that catalyzes the conversion of S P. The kinetics of P formation follow MichaelisMenten kinetics. If the KM value for this enzyme is 4.0 M, what is the value of O at (S 8.0 M. . e 0.25 . 0 0.50 e 0.75 e 1.0 . D. . Cannot determine from the information given.

A 22.8 ml. sample of a 0.400 M aqueous hydrocyanic acid solution is titrated with a 0,409 M aqueous potassium hydroxide solution. What is the pH at the start of the titration, before any potassium hydroxide has been added pH 3D

The following electrochemical cell has a potential of 0.324 V at 25 C. Pt H2(g, 1.00 bar) H(aq, 1.00 M) CI(aq) AgCI(s) Ag CI M

Which is the unambiguous criterion for a reaction to be considered spontaneous AH 0 O AH0 O As0 OAG0 O AG 0

Provide the major organic product of each reaction.

1. MCPBA (a) 2. CH,CH,MOBr 3. Diute H. HO (b) excess HCI

Provide the major organic product of each reaction.

1. Brg. H0 1. KOH (cd) 2. KCN, H,0

Provide the major organic product of each reaction.

H0.H CH,CH,0 K (e1) CH,CH,OH

Provide the major organic product of each reaction.

SK CH,NH, (hi) 2. H20. H

Provide the major organic product of each reaction.

CH, 1. LIAIH, HBr (K) 2. H,0

Provide the major organic product of each reaction.

O Na CH,CH,Br (1) (m) Br Br 2 equiv. CH,CH,S K

Complete the table. Place about 2 g of tartaric acid previously dried and accurately weighed in a conical flask. Dissolve it in 40 ml of water, add a few drops of phenolphthalein TS, and titrate with 1 n sodium hydroxide. Each ml of 1 N sodium hydroxide is equivalent to 75 mg of tartaric acid. *Note: Volume of sodium hydroxide was observed at 26.5

Among compounds B to E, shown above, which one(s), Will undergo mutarotation Will definitely Not give positive results with Fehlings and Tollens tests Will give an aldaric acid with nitric acid Will give an aldonic acid with Brz in water Between B and C which is most stable OH OH OH HO OH HO OH OCH, B E D.

You are a biochemist studying the lactase enzyme, and you are purifying the enzyme from a bacterial lysate. After an initial ammonium sulfate precipitation step followed by dialysis of your sample, you are optimizing a chromatography using a stationary phase composed of diethylaminoethyl cellulose (which contains ionizable amino groups) and a

Absorbance (280 nm) 3 1.2 10 0.8 0.6 0.4 0.2 mobile phase gradient m N N 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50 FRACTIONS Enzymatic Absorbance (UmL)

Mass of pdichlorobenzene in Melting tube.. 0.0100kg Mass of opened sample tube UNKNOWN. 58.575 g Mass of sample tube UNKNOWN sampie 1. u 57.905 g. Mass of sample tube with remaining sample. (should be approximately the same as above but check it) Mass of sample tube with both samples removed. 57.905 g. 56.795 g Here are the melting points

Identify one of the two products that is expected in the following Cannizzaro reaction H 1. KOH 2. 0 A) O B) HO O D) HO

For a chemical reaction that is spontaneous in the reverse direction, it is found that ASsys 0. This ear (Please note that in the answer choices the magnitude means comparing the absolute values) 2 ASsurr O and its magnitude does not matter. ASsurr O and its magnitude does not mater. O ASsurr 0 and its magnitude is ASsys. O ASsurr O and its

Give the systematic name for this structure.

Draw the products of the following reactions. acid a. NH NH2 b. acid H CN C. HCN TSOH d. CH, (ess) HCCH OPP3 .

Cnsider the following reduction halfreactions, at 25C. x(aq) 3 el X(s), E 0.94 V y2(aq) 2 e Y(S). E 0.87 V a) Calculate Ecel 0.911 b) Calculate AG(reaction). 439 kJmol c) Calculate In(K), where K is the equilibrium constant. d) If a galvanic cell is initially setup at standard concentrations, what is the equilibrium concentration of V1. e) If

Empire, Inc., replaced its truck-and-dolley system of moving inventory around its plant with a computer-controlled conveyor system. The costs associated with this equipment replacement were as follows: Purchase price of conveyor system $2,300,000 Book value of truck-and-dolley system 40,000 Installation cost of new conveyor system 225,000 The

In the m. Auve, assum the ove no unerpeced Sa veactos A five (6 four ) thme tue Sauvoe acia, but ou anp g Sae of he Saing tene acd an Severa 2) epermeni to Seturet, e feny gea belau ( Helps), you omiy OLAS w j One or tuo Of he CC bous euca Houu many dienes cala be Ho. When amide Puenal umn you by dentyze it under base cotons ONone yak 3)

What steps would you take to carry out the following transformations . COOH b. .COOH

Draw the following. a. methylsuccinic acid b. 2,3dichloro2methylpropionic acid c. 3,3diethylglutaric acid d. 2oxoadipic acid

Molybdenum disilicide (MoSiz) has a body centered tetragonal structure (a 3.206) with the following motif Mo 0,0,0 Si 0,0,13 0,0,23. The density of MoSiz 6.26 gcm. The atomic mass of Mo is 96 amu and Si is 28 amu. If CuKa radiation (2 1.54 A) is used, determine the Bragg angle of the reflection with the largest structure factor.

What is the chemical difference between glucose and F2-Glc?

The following are from a class of biological molecules known as prostaglandins. Which would you expect to absorb at the longest wavelength in the UV The shortest OH CH, CH, CH, OH OH C05954 C04685 C06438 A1 B2 D1

Provide 4 possibilities for acid catalysts?

Water Quality in Local Waters Determination of Phosphorus Content in Surface Waters Construction of Beers Law Plot Phosphorus Conternt (mg PL) Alsorbance 0.00mglA 0.05 mah 0.10 maL 0.75 malh 0.00 Blank 1.02 Standard Solution 1 0.05 Standard Solution 2 0.10 Standard Solution 3 0.50 0.30 Standard Solution 4 Attach Beers Law Plot to the data sheet

A water sample at 25 C presents the following chemical characteristics Ar0 mgL CaCO, Au75 mgL CaCO, Acidity2 meqL Ca60 mgL Mg 36 mgL The stability index according to Langeler is 0.15. Calculate 1) The pH of the water 2) The aggressive CO, 3) The calcium carbonate hardness K,4.47x107 Atomic weight H1, 016, Ca40, Mg24, C12

Propose a structure for the substance of molecular formula C 7 H 14 O (IV 1715 cm -1 ) that is compatible with the 2D NMR (COSY) spectrum below. Indicate the correlations in the contour map below, number the signs according to the drawn structure.

ll (ppm) 2.8 2.6 2.4 2.2 2.0 1,8 1.6 1.4 1.2 1.0 0.8 0.6 2.8 2.6 2.4 2.2 2.0 1.8 1.6 1.4 1.2 1.0 o.8 o.6 (ppm)

Indicate 5 ways that you will verify that you indeed synthesized cyclohexane.

The following pharmacokinetic parameters were determined following the oral administration of Drug A: Systemic clearance (CLS) = 9 L/hr Fraction excreted unchanged (fe) = 0 Bioavailability (F) = 45 % a) Showing all working and stating all assumptions, determine (i) the proportion of Drug A that is absorbed from the gastrointestinal tract (fg), and

Aluminum gallium arsenide (Al,GaxAs, where 0x1) is an important optoelectronic alloy. The crystal structure consists of a facecentered cubic lattice with As atoms at 0 0 0 and Al or Ga atoms at 141414. The atomic numbers of these elements are ZAI 13 ZGa 31 ZAS 33. Assume that the position is randomly occupied by Al or Ga with a fractional

Concern the structure of various substances, at 0C, which may consist of A widely-spaced molecules B molecular crystals C widely-spaced atoms D a giant structure of ions E a giant covalent structure Select, from A to E, the structure of the following. Each letter may be used more than once or not at all 1. helium 2. iodine 3. diamond 4. carbon

Formulate the potential product of each of the following reactions. Write "no reaction" where appropriate. Determine the R/S designation for both starting materials and products in the following SN2reactions.

b) c) d) e) NH CH NaSCH 3 HS Csl LICI CH3OH CH3OH SCH3 NqOH CH3CHOH DMSO

7. the pKa of free-floating lysine's side chain is 10.4. In one position with a protein, the sidechain exhibits a pKa of 5.3. If we compare 500mM of both lysines in water, how many hydronium ions will we expect to see in the free-floating lysine solution? 8. the pKa of free-floating lysine's side chain is 10.4. In one position within a protein,

The tertiary structure of proteins are maintained mainly by: Van der Waals interactions hydrophobic interactions H bonds ionic interactions which one is correct?

1. What are the nudear charges (NC) and effective nuclear charges (ENC) for the following atoms Give your reasoning. a) Sr b) P C)I

A mixture consisting of 0.130 mol N, 0.041 mol O, 0.100 mol CH, and an unknown amount of CO occupies a volume of 8.90 L at 25C and 1.09 atm pressure. Find the moles of CO are there in this sample.

If a buffer solution is 0.480 M in a weak acid (K, 8.1 x 106) and 0.220 M in its conjugate base, what is the pH pH 3

Consider the reaction 2 SO2(g) O2(g) 2 SO3ls) at constant temperature. Initially a container is filled with pure SO3(s) at a pressure of 2 atm and the reaction is allowed to proceed until equilibrium is reached. If y Po2 at equilibrium, what is the value of Kp expressed as a function of y (2y) (v)(y2) (2 y) (2y) (y) (22) (v)(2y) (22y) (2y) (y)

What is the product of the following reaction? A) I B) II C) III D) IV

NH2 (2 equivalents) I ccCHCH, H H cCCHCH, HH CECCH,CH CCCH,CH, IV

What is the product of the following reaction? A) I B) II C) III D) IV

NH2 (2 equivalents) I ccCHCH, H H cCCHCH, HH CECCH,CH CCCH,CH, IV

Explain ,What is the product of the following reaction? A) I B) II C) III D) IV

NH2 (2 equivalents) I ccCHCH, H H cCCHCH, HH CECCH,CH CCCH,CH, IV

What diene and dienophile give the following DielsAlder adduct CN H3CO

Draw the mechanism for this reaction. AlC3 CI HCI

Show the reagents and intermediate structures for the synthesis of each of these structures from benzene. . . Br b. C. OH

What would be the major product of this reaction and why 50 C BrBr

Give products for the following reactions. (Some may have more than one.) Cl, a. hv b. H3COH CI AICI, C. CI d. 2 Li 2NH3

Which is not a product of this reaction NBS hv O 4bromo2methylpent2ene O (2E)1bromo2methylpent2ene 3bromo2methylpent1ene O 3bromo2methylpent2ene

Draw the mechanism for the Birch reduction of benzene. Na, NH(1) CH,OH

Draw the SN1, SN2, E1, and E2 reaction mechanisms of (just do all four reactions for each) A. (2R,3S)2bromo3chlorobutane reacting with sodium hydroxide B. (3S,4S)3bromo 3,4dimethylhexane with NaF

Write a chemical equation that could be used to represent the incomplete Combustion of heptane. Then write the chemical equation for the complete combustion of heptane. Compare and contrast these chemicall equations.

Predict the major products for the following transformation HS HS .S SH S S 1. LiH 2. S SH II S S SH S 0S0 S. IV S SH,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

Predict the major products for the following transformation HS HS .S SH S S 1. LiH 2. S SH II S S SH S 0S0 S. IV S SH,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

Predict the major products for the following transformation HS HS .S SH S S 1. LiH 2. S SH II S S SH S 0S0 S. IV S SH,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

Predict the major products for the following transformation HS HS .S SH S S 1. LiH 2. S SH II S S SH S 0S0 S. IV S SH,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

Predict the major products for the following transformation HS 1. LiH S 2. HS SH SH S. SH S. S. S. S. OS0 S. SH II II IV ,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

Predict the major products for the following transformation HS 1. LiH S 2. HS SH SH S. SH S. S. S. S. OS0 S. SH II II IV ,If benzyl phenoxide is mixed with large excess of hydrobromic acid, what isare the products of interest obtained from this reaction a) benzene. b) toluene. c) phenol. d) benzyl alcohol. e) benzyl bromide. f) bromobenzene. g)

What is the molarity of the solution of sodium hydroxide in water used? 5g of sodium hydroxide 50ml of distilled water

Which of the following functional groups will appear in the range 160220 ppm in 13C NMR A) ethoxy group B) aromatic carbons C) carbonyl group D) methoxy group

Select the compound needed to give the product shown in the following reaction. MGCI 1. 2 H30 A) O B) D) OH

HH GO HN H H GY H OHN CH H CH C INTERACTIONS STABILIZING PROTEIN STRUCTURE (SIDE GROUPS) Hbonds CH HN CHCH A 19 CH CH 8 9. Circle all peptide binds each aa 4 Van der Waals Interactions CH CH 1 HC CH HC CH de cual Le CH CH 8 His Hydrophobic Interactions CH FH 8.0 (Phor CH, Na Electrostatic Interactions HC LAN bue HO CH NN Hydrogen Bonding NHOC

Why does dibenzalacetone have 3 stereoisomers?

1. If it takes approximately 5.92 x 10 17 molecules of ATP to flex your toes one time. How many times can you flex your toes with the number of ATP molecules from question 3? 2. (Solid Iron reacts in the presence of oxygen to make Iron (III) oxide. If 50 g of solid iron reacts with 50 grams of oxygen how many grams of iron (III) oxide are

In the following reaction, 5.4g of benzaldehyde was reacted with 1.5g of acetone. Show the calculation for the moles of benzaldehyde, the moles of acetone, the theoretical yield of dibenzalacetone in grams.

2 Sodiem Hydreside Benraldehyde Acetene Dibenalacetone MW214.30 pml MW 106 13 gmol P178 C Den L04 gml. MW S0 uimol BP 56C Den0.0 giml.

In the following reaction, 5.394g of benzaldehyde was reacted with 1.477g of acetone. Show the calculation for the moles of benzaldehyde, the moles of acetone, the theoretical yield of dibenzalacetone in grams.

NaOH 2 Sodiem Hydreside Bearaldehy de Acetee Dibenzalacetune MW214.30 pml MW 106 13 gmol P178 C Den 104 gml. MW SO ymol Den0.790 gml.

a. Calculate the Enthalpy of Reaction for the neutralization reaction between hydrochloric acid and sodium hydroxide shown. NaOH(aq)+HCl(aq)NaCl(aq)+H2O(l) n b. What will be the enthalpy of reaction before the neutralization of 0.05 mol of HCl with 0.05 mol of NaOH? c. If this reaction is performed in a coffee cup calorimeter in 100.0 g of water,

Using the master equation for the titration of a strong base with a strong acid, prepare (in MS Excel) a family of curves (pH vs Va one plot, three curves) for the following titrations a. 50.00 mL of 0.0200 MNaOH being titrated with 0.100 M HCI b. 50.00 mL of 0.00200 M NaOH being titrated with 0.0100 MHCI and c. 50.00 mL of 0.000200 M NaOH being

2. The concentration of NaOH solution used in Part 1 was determined to be 0.193 molL. In the titration of the strong acid with NaOH, the volume of the strong acid solution in the flask before titration was 25.00 mL. Calculate the molarity of the strong acid solution used in the titration from the volume of NaOH required to reach the equivalence

What is the major organic product for the following reaction HO H2OH,SO4

Write an R function from scratch to conduct forward selection. Your function should allow the following user-specified options: selection based on adjusted R2 , AIC, as well as BIC. You can use built in functions in R like lm() or summary() but you cannot use any functions dedicated to model selection like step, etc. Need to handle continuous

Calculate the cell potential at 25C under the following nonstandard conditions Sn2 (aq) Mn(s) Sn(s) Mn2(aq) Sn2 0.08M 3D Mn2 1.15M Record to the nearest hundredth of a V. 3 Hostion 38

2) Draw the structures of crystal violet in aqueous media at pH 2, 7, and 16. 3 3) Explain what is required for both Malachite Green and Crystal Violet to act as chromophores. 4) Based on your answers to Q2 and Q3, rationalize the pHdependency of the UVvis absorption spectra of the product dyes (what color(s) do you see and what causes any

If you have valuation curves, how is it obtained later, the graph of Gran Plot? What are the steps to make a Gran Plot graph? Please help.

1. Why was it important to filter the saturated solutions before taking the pH readings? 2. During the video it was mentioned that the pH of Cu(OH)2 usually is 5.50. Why does is the pH so low? 3.For Cu(OH)2, Ba(OH)2, and Mg(OH)2 the pH values determined were not exactly accurate.What error was done in the procedure that caused these inaccuracies?

A gas has pressure ( 1 bar ) , temperature ( 15 C) and density ( 1,855 kg m3 ). Calculate the value of R when heating (0.9 kg) of this gas from a temperature of (15 C) to (250 C) at a constant pressure, and the required temperature is (175 kJ). Calculate Cp and Cv and calculate the change in internal energy and work A transferred

What is the molecular structure of SCN O trigonal planar O trigonal pyramidal O tetrahedral O linear O Vshaped

Which substance on the solubility curve is the most soluble at 75C?

Calculate the equilibrium constant from the standard free energy change. Using standard thermodynamie data (linked), calculate the equilibrium constant at 298.15 K for the following reaction. H,(g) Cl,(g)2HC(g) Check Submit Answer Show Approach

Determine the volume at the equivalence point from the graph above.Report the value of the slope and intercept.

Grans Plot Titration Between HA and NaOH 0.0001 0.00008 0.00006 0.00004 0.00002 21.00 15.00 0.00002 16.00 17.00 18.00 19.00 20.00 0.00004 y 2E05x 0.0004 0.00006 Volume of NaOH (mL)