Chemistry Questions and Answers April 22, 2020

A. Find the energy levels for a particle in a 3D box. Explain, providing examples, why states lose their degeneration when the box is no longer cubic and becomes a rectangular box. Evaluate the cases in which a b c and a b c. BA crude treatment for the n electrons of a conjugated molecule considers these electrons to be particles moving in a

If a H2 molecule rotates in the plane of a crystalline surface (in a chemisorption situation), it can be approximated as a two-dimensional rigid rotor. Calculate (in kJ/mol) the lowest energy rotational transition (transition from the J=0 to J=1) for such a system. Take the reduced mass of the rotor to be 8.3678 x 10-28 kg and the value of r to be

Chemistry A Describe location on the xaxis of a CH stretch for an alkene VS the corresponding stretch for an alkane. B A student mentioned that they did not want to run a sample in a IR, due to the radiation would smash their sample by breaking bonds.is this student have a valid point Describe..

Consider the physical situations described below and propose a reasonable quantum model (for example, rigid rotor, Particle in a Box, etc.) to describe each situation. Please name only one model for each problem. Explain your reasoning with one sentence for each model you choose. (a) An electron is moving in the -clouds of the benzene molecule.

(a) What is the main assumption of the Born-Oppenheimer approximation? (b) Using the Born-Oppenheimer approximation, write the Hamiltonian for the H2 molecule (also, draw the diagram). Indicate the attractive, repulsive potential energy terms and the kinetic energy terms.

(i) Write the general expression for the energy of a harmonic oscillator. (ii) Calculate the zero-point energy of a harmonic oscillator consisting of a particle of mass 2.33 10-26 kg and force constant 155 N/m. (iii) Consider a simple harmonic oscillator with mass m and force constant k, and a particle with the same mass in a one-dimensional box

(a) For Hydrogen atom, Bohrs approximation to the energy ( En= -Z^2/n^2 13.6 ev) gives results close to the experimental results. If the absorption spectrum of the H-atom shows that the electron is excited from the ground state to 4TH excited state, calculate the energy of the incident radiation. (b) Once an electron gets excited its angular

Calculate the retention indices for two components in the solvent mixture sample. Use the C8C13 alkanes as your markers for retention indices calculations and also compare results with the literature data. Temperature programming was used. Show Working.

x109 EI TIC Scan Mixsf D 1.1 1 0.9 08 07 0.6 05 04 03 02 01 0 35 6 65 75 85 95 10 105 1 115 12 125 13 135 14 145 1s 15 Counts vs. Acquisition Time (min) 35 4 Peak TR (min) Peak Identity from library match 3.638 Toluene Hexane, 2,4dimethyl 4.088 4.819 Benzene, chloro 5.191 OXylene OXylene Hexane, 2,4dimethyl 4 5.564 5.67 7 6.217 Benzene, bromo 8.

The 4 As atoms are la belled, All other atoms Ga are As As .Lo.0,0) a The figure above shows the structure of GaAs. It is very similar to the diamond structure, but some of the atoms are Ga and some of them are As. (a) Define a set of lattice vectors and basis that can be used to describe the crystal structure. For the lattice, in additional to

The mechanism for the decomposition of gaseous NOCl is NO,CI NO, Cl k2 NO,CI Cl NO2 Cl2 By making a steadystate approximation for Cl, express the rate of appearance of Cl, in terms of the concentrations of NO2CI and NO2.

Determine the mass specific internal energy (u) of the following two substances at the given conditions. Also determine which (if either) of these substances can be wellapproximated as 1) a thermally perfect gas at these conditions 2) an incompressible substance at these conditions and 3) a calorically perfect substance over the temperature range

Identify 4 ways that you can help in your current or planned position to help your organization adjust to better compete using information technology based on the information you've obtained in this course(Please see the attached document).

Go into two different retail stores and compare the following features: lighting, flooring, shelf fixtures, signage, help/service, image, ambiance.

For a reservoir containing oil and a free gas cap, as the one shown in the figure below by using the above gradients, find the pressure distribution shown on the left-hand side of the diagram. ? What is the pressure at the Oil-Water Contact (OWC) at 5500 ft? ? What is the estimated normal temperature at that Depth? ? What is the pressure in the

Apowers oploration Screen Captve Pro WATER OIL Owc 5500 GAS GOC 5200 TEST RESULTS at 5250 ft Po 2402 psia dpo dD 0.35 psift

A sealed vessel contains a mixture of 956 g of trichloromethane chcl3 also called chloroform and 230 .g of ethanol ch3ch2oh.At 30-degree Celcius assume that their vapor pressures are 36.0 kpa and 13.0 kpa respectively .find the composition of the vapor above the solution in terms of mole fractions at 30-degree Celcius.

An aqueous potassium iodate ( KIO 3 ) solution is made by dissolving 513 grams of KIO 3 in sufficient water so that the final volume of the solution is 290 L Calculate the molarity of the KIO 3 solution

9) Complete the mechanism below. You have a freebie at the top to get you started. But, for every other base or acid needed, include a realistic amino acid side chain (not just B or AH). Lys HO OPO HO HO HO CHOH

CH3 HC HC, and H. H H3 H3C H3 H. Select one a. different molecular formulas b. constitutional isomers O C. stereoisomers d. identical

Convert 565dg kg Be sure to solve this problem using unit analysis (think train tracks) in at least 2 steps for credit. Enter your answer in the textbox with units, but be sure to save your work and upload it after the exam for credit.

A 5 mL wastewater sample is put in a standard 300 mL BOD bottle, and the bottle is filled with dilution water. The bottle had an initial dissolved oxygen concentration of 9 mg/L, and a final dissolved oxygen concentration of 3.5 mg/L. A blank (a BOD bottle filled with dilution water) run in the parallel showed no change in the dissolved oxygen in

Flue gas (the gas that leaves a smoke stack after combustion) has a significant amount of COz that is typically released to the atmosphere. The composition of the hot combusted gases coming out of a coalfired power plant is 18.0 CO, 3.0 O2, and 79.0 Na (all percentages are on a mass per mass basis). The first step in the process is to pass the

Prelaboratory Assignment I. Give the step-by-step procedures that you will use for the following tasks: a. Measuring the density of the metals b. Measuring the heat of fusion of ice

A. From what group must the terminal atoms come in an ABx molecule where the central atom is from group 6A, for the electron-domain geometry and the molecular geometry both to be trigonal planar? Answer in American notation B. From what group must the terminal atoms come in an ABx molecule where the central atom is from group 7A, for the

If the internal pH of a muscle cell is 6.8, what is the [HPO4^-2]/[H2PO4^-1] ratio in the cell? (pKa of H2PO4^-1 is 7.2, pKa of HPO4^2- is 12.4).

How many moles of aluminum are necessary to generate 4.88 moles of aluminum oxide, according to the following equation: 4Al+3O22Al2O3 Your answer should have three significant figures.

When 15.0 mL of a 1.53x104 M nickel(II) acetate solution is combined with 18.0 mL of a 3.1910M potassium carbonate solution does a precipitate form (yes or no) For these conditions the Reaction Quotient, Q, is equal to

How much kinetic energy (KE) does an object with a mass of 1.200 x 10 g traveling 1. in a straight line with a speed of 5.0 x 10 m s possess 3. A sample of zine weighing 425.0 grams initially at a temperature of 25.40 C required 1360.0 joules of heat energy to increase the temperature to 33.70 C. What is the molar heat capacity of the zine 4. The

Chemistry A solution was prepared by mixing 75 g of glucose in 250 g of water. What is the concentration in terms of by mass Group of answer choices 54 23 30 70

8. A5.00 L tank contains a mixture of 27.5 g of axygen gas and 38.5 g carbon dioxide gas at 32 C. Calcutate the partial pressure of oxygen in the container. (1 Point) O 200 am 622 atm 4.31 atm 8.69 atm 746 atm O O O

Problem 4. The antitumor agent bizelesin was found to form interstrand crosslinks at the underlined positions within the doublestranded sequence GTACTAAGT in the p53 gene. Suggest a plausible arrowpushing mechanism for the formation of DNA crosslinks and include the structure of the final crosslinked adenine bases. (hint a strained ring in

1. Design primers that will amplify the following region of DNA. The primers should be 15 bases in length and indicate the 5 and 3 ends of the primers. 5-GCGATCGGCTCAACTCGATCGAGATCCTCCTGATGATGCGCAGCCGCGTTAA-3 2. In PCR we employ a three-step thermal cycle. What is the purpose of each step and what approximate temperatures are used? 3. Write the

1 The data below are for the chemisorption of hydrogen on copper powder at 25C. Confirm that they fit the Langmuir isotherm at low coverage, Then find the value of K for the adsorption equilibrium and the adsorption volume corresponding to complete coverage pPa 25 129 253 540 1000 1593 Vem3 0.042 0.163 0.221 0.321 0.41 0.471 6 The adsorption of

Chemistry A one-electron atom is an atom with Z protons in the nucleus and one electron. For example, Z = 2 for helium and Z = 3 for lithium. Use our class discussion of the allowed radii and energies of the hydrogen atom with Z =1 as a guide to answering the following questions where the atom has Z protons and one electron. Represent the electron

Chemistry A chemist synthesizes a copolymer containing 90 mole % isoprene and 10 mole % methyl methacrylate. In a systematic manner, describe the polymer chain microstructures that are theoretically possible. (Ignore limitations due to chemistry, which we have not considered yet.) Be careful! There are many possibilities.

1) DIBAL 2) H3O,H2CRO, (aq) (excess) SOCI2 TEA,1) CH3CH,ONa, (1 eq) CHCH,OH H20, H2SO, heat 2) H3O,1) CH3ONA, CH3OH 1) CH3ONA, CH3OH OCH3 2) 2) Br 3) H3O

32. In each case, determine the requested property values and show the states on carefully labeled pv and Tv diagrams (a) For H20 at 5 bar, 245C, determine v in mkg and u in kJkg. (b) For Propane at 120F, 0.6413 ftlb, determine p, in Ibfin. (c) For Ammonia at 20F, u 573.10 Btulb, determine p in lbfin. and v in ftlb. (d) For H20 at 2 bar, x 0.8

The complex [(C18H18N4S)]HgBr2] crystallizes from solution in acetonitrile (CH3CN) to give triclinic crystals with a unit cell volume of 1113.5 3 and a density of 2.16 g.cm-3. Calculate the number of molecules of complex per unit cell and the number of molecules of solvent (if present).

Chemistry Which of the following structures is more basic? Show your work to explain why and give a brief explanation.

VS CH3 CH3

Chemistry 1- Which method is used to determine the EMF of a galvanic cell? And what\'s the principle? 2- What the results would be if KCl solution in the (SCE standard calomel electrod) were not saturated? .

Specify the formal charges on the atoms labeled ac in each structure. b c H3CCHCH2 a b H3C EN 1 a b 1 b

Freezing points of solutions Sample 1 C AT C Mm Samples 1 2 C AT C Mm ,3. Freezing points of the solutions Date Sample Mass of paper solute (g) 2 26782 0.4276 0, 2506 Mass of paper (g) 0.5443 Mass of solute (g) 0. 4431 Sample 1 0.1012 Sample 1 2 Time Temperature (C) Time Temperature (C) 14.7 13.5 10.7 10.2 30 6.4 49 4.0 45 5.8 4.7 4.1 45 60 90

When you purchase T 4 DNA Ligase, a 10X buffer (400mM Tris, pH 7.5; 200mM MgCl 2 , 100mM dithiothritol, 70mM ATP, 450ug/ml bovine serum albumin) is supplied with it. What are the final concentrations of MgCl 2 and bovine serum albumin when you use the ligase enzyme to perform a ligation reaction? SHOW WORK

Stoichiometric equations can be used to represent the growth of microorganisms provided a molecular formula for the cells is available. The molecular formula for biomass is obtained by measuring the amounts of C, N, H, O, and other elements in cells. For a particular bacterial strain, the molecular formula was determined to be C4.4H7.30,2No.86.

Calculate the pH of a buffer solution prepared by dissolving 8.5g of NaH2PO4 and 10.18g NA2HPO4 in 1 L water. NaH2PO4 * H2O MW= 138; Na2HPO4 * 7 H2O MW= 268 pka= 7.21.

Task 1. 10 ml of an aqueous solution of phenol with a concentration of 10.0 mgl was irradiated with a dose rate of 4.4 Radsec. After 1 hour of irradiation, the phenol concentration reduced to 2.7 mgl. The density of phenol is 1.07 gml. Calculate the radiationchemical yield (molecules100eV) and the degree of phenol degradation ().

9. I have two mystery samples of the same polymer synthesized using chain growth polymerization. One exhibits a high melting temperature and stiffness the other is much more compliant and has a lower melting temperature. The chain growth polymerization routes were different. Draw the structures of the two polymers and explain what could have

the products of the following reaction are:

1) 03 (2) CH,SCH, Seleccione una o ms de una H.

Which of the following is an example of a physical cost Oa. Mental effort Ob. Fatigue O c. Feelings of inadequacy d. Social Embarrassment e. Perceived Risk

Draw the Molecular Geometry of NO2 and CO2 . Next draw in the individual dipoles for your structures, if any. Finally indicate if there is a net dipole or no net dipole for the compounds Draw the other resonance structure of the following Lewis Structure. Circle the most stable resonance structure and explain why? Be sure to include curly arrow

2. SO 4. (CH3)AN 5. CO2 1. CO3 3. NO2

Imagine that you show up for a job interview at a pharmacist. This company produces a medicine whose active ingredient is a monoprotic weak acid with formula CH303, molecular weight of 230.259 g / mol and pK, = 4.15. They ask you to describe in detail how you would prepare 500 mL with an analytical concentration of 0.0288 M of the active

Q1 conservation of mass 0.3 Points Remember americium241 Its an isotope that can be used in a radioisotope thermoelectric generator (RTG) to power spacecraft. Why While plutonium238 is generally considered better for RTGS, theres currently a global shortage of it. The radioactive decay for americium241 is this 241 Am Np a. 237 95 Use the periodic

The solution of Propranolol Hydrochloride (Mr = 295.8 g mol^-1) with a concentration of 1.80 g/L was prepared. Predict the theoretical pH of precipitation for this solution. Measurement Record the pH of drug solution 3.9 The initial volume of NaOH (mL) 2.10 The final volume of NaOH (mL) 3.50 The total volume of NaOH used (mL) 1.40 pH at

Questions 1. Using the structures and polarity properties of the lipids in this lab, please explain the observed order of migration of the lipid standards. 2. What reaction occurs if you boil olive oil in sodium hydroxide What new lipids would be made and how would they migrate on this TLC plate 3. The first solvent was run half of the distance of

Which one of the following has highest value for H2O than D20 by comparing physical properties (A) Viscosity (B) Dielectric constant (C) Temperature of maximum density (D) Enthalpy formation

For storage of dihydrogen which of the following metal cannot be used in the preparation insulated tank (A) Mg MgH2 (B) Ti TIH2 (C) Na Naz (D) Na Niz

A mixture of ammonium sulphate and sulphuric acid is 11 molar ratio is electrolyzed using platinum electrodes. The products formed at anode and cathode are respectively (A) 2 nd NHSO () 22 nd Hz (C) (NH4), S2Os and H2 (D) H nd H,02

Compare the properties of H2O2 in Gas phase and solid phase which one is incorrect (A) OHIN solid phase is greater than in gas phase (B) 0O bond length in gas phase is highest than in solid phase (C) Dihedral angle of H2O2 in solid phase is greater than in gas phase

Which one of the following is not suitable for preparation of H2O2 by the action of dil acids at cold condition (A) Na202 (B) Pbo2 (C) Bao2 (D) K202

In which of the following reaction H202 acts as reducing agent (A) I2 H2O2 OH (B) Mn2 H2O2 (C) PbS H202 (D) FeSO4 H,O2 H2 SO4

1270k ACg) Big) H20 ) Ces H20 AL9J Cig) catalyst Choose correct statement for aboue Conuersiion. A) The percintage of He Can be Ancreased by adding Nau Feo4 B BLg) and Clas haue Zero dipole homent c) The process of polmation of Alg) and Cgj is calued Coal gasigication D) The omation of Aca) and Bigj is also obtained octton 1276 K by Ni

Write a cation exchange reaction depicting the exchange that takes place when AICI3 is added to the humus extract?

PART 3 Flocculation Humus 1. Dilute the remaining 5 ml of humus extract to 20 ml. 2. Place 5 ml of diluted humus extract in each of 4 test tubes and fill the tubes 23 rds full with distilled water. 3. Add 10 drops of 0.5 N KCI to the first tube, the same amount of 0.5 N CaCl2 to the second, 0.5 AICI3 to the third and nothing to the fourth tube. 4.

3. (4 points) You have recently isolated a protein and are currently determining the structure of the protein. Gel filtration chromatography indicated a molecular weight of approximately 320 kDa. Treatment with a low concentration of guanidinium hydrochloride (not enough to fully denature the protein) followed by gel filtration chromatography gave

Complete the following table:

Lab Notebook Trial 1 Trial 2 Trial 3 Volume of HCI 100 ml 100 mL 100 mL Initial temperature of HCI 25 C 25 C 24 C Volume of NaoH 100 ml 100 mL 100 mL Initial temperature of NaOH 25 C 25 C 24 C Final solution temperature 40 C 40 C 39 C Wast Moles of H mol mol mol Moles of OH mol mol mol Limiting reagent Select Select Select Heat transfer for

Consider the reaction of synthesis gas over the 3d transition metals. Indicate the main carbon-containing products formed during CO conversion on Fe, Co,Ni, and Cu and explain the differences in terms of atomic binding energies.

5. (8 pts) The Hydrogen Atom. You will need Table 14.2 to complete the following problems. (a) Calculate the probability that a 1s electron in a hydrogen atom will be found within (less than or equal to) the Bohr radius, ao. You will need the following integral relationship... ax2 2ax 2 xea ax dx eax a3 (b) How many radial nodes occur for the

Question 19 1.5 pts For reaction CH3CH2CI OH CH CH OH CI The activation parameters in Arrhenius equation are A 1.4 X 10sl and E, 28.2 kJmol, respectively. What will the rate constant be at 40.C E. A. ezp Type numerical answer WITHOUT UNIT. 1 pts Question 20 For reaction 2A B 20, the following mechanism has been proposed

Hydrogen adsorbs dissociatively on most d-metals, e.g., Pt and Rh; explain why, based on the very simple molecular orbitals of the dihydrogen molecule.

Pt is a catalyst for the (simplified) reaction: NO + H2 NH2OH The surface of the Pt particles contains identical sites only; propose and motivate a scheme of elementary reaction steps for this overall reaction, according to the LangmuirHinshelwood mechanism.

Draw the structure of this compound.

IDD 2120 ng 3400 1368 3303 2987 1170 4000 3000 2000 1500 1000 BAVENUNBERI TRINSHETTRNCEIS

do H If this bond can rotate, select all of the structures that a 180 bond rotation could make. H. Il. H Dont Knoyw Submit ,Examine the highlighted labeled bond in the structure below. do Can the highlighted labeled bond rotate 180 without breaking any bonds in the molecule O yes Ono ,

Rank the following from most acidic to least acidic (L to R) A. CH3OH B. CH3NH2 C. CH3COOH D. CH30 O ACBD CABD DBAC BDCA DBCA

The mass of my empty beaker is 53.18g, and the mass of the beaker & water is 132.36g. Calculate Mass of the water, the volume of the water, and calculate density.

80 3. Determine the density of 0 ml of deionized water using a beaker and a 100 ml volumetric flask. Do three separate determinations and calculate an average density. Record your data and calculated values to the correct of significant digits and with proper units. For the digital balance, record the display. For the beaker and the volumetric

A researcher is interested in determining the detection and quantitation limits of a method for the detection of thallium. Ten method blanks gave the dimensionless instrument readings 81.9, 46.1, 38.9, 50.9, 95.9, 36.7, 88.7, 74.3, 41.3, and 82.1. Ten samples containing a low concentration of thallium near the detection limit had a mean reading of

could you please help to draw the mechanism with the amino acid for condensation reaction mechanisms please ?

0 HOP0. L0 I 0 CH3

Discuss the main catalytic reaction steps used to convert natural gas into high-purity hydrogen; provide for each step the reaction equation, indicate whether it is exotherm or endotherm, indicate a typical temperature, and propose a suitable catalyst.

Give the three main reactions catalyzed in a catalytic convertor placed in the exhaust of a gasoline car.Why is Rh needed to reduce NO?

Describe the concept of shape selectivity in zeolite catalysis and give one example.

Use the following scheme to answer this problem and the next. Draw the structure of compound A. Question 8 Br2 Brz B Br Br A CH,OH Create OscorSketch Answer 8 Draw the structure of compound B. Question 9 Create OscerSketch Answer 9

Which will be the quote of year 4 of a loan of an amount of 5,000,000, 5 years term 2% interest rate, an amortization of 25% balloon and the rest flat during all years of the loan?

Deprotonation of Luminol. Provide the complete mechanism that shows the deprotonation of the luminol zwitterion to form the dianion. You must include appropriate arrows, intermediates, and formal charges. The ChemDraw template of this document is available on Carmen. (4 pts) NH, NH2 N. NaOH NH H20 luminol luminol dianion (zwitterionic form) Z

Predict the Product. Provide the stable organic product(s) that would result for each reaction below. Label the product formed in highest yield as major. (3 pts each 9 pts TOTAL) 1. Na,S,0., NaoH, 100 C 2. CH,COOH NO2 H2N H2N triethylene glycol, 210 C NO2 1. Na,s,0.. NaOH, 100 C HO. 2. triethylone glycol, 210 C

Chemistry Explain why a basic solution of methyl ethylamine is neutralized by the addition of a concentrated hydrochloric acid, its weak absorption band centered at 244 nm starts to disappear.

Shown are four Lewis structures for ozone (0,). Match each structure (on the left) with the correct response (on the right). A. 10001 B. 10i c. 1000 D. 100O Drag and dine optians an the rght hand side and mit. For beybeard navigation tho Mare Structure A Has too few valence electrans Structure is a correct Lewis Structure Structure C Violates the

b) What are the formulae of the following compounds consisting of linked octahedral and tetrahedral units. In each case you must draw the structure and explain how you determined the formula. (i) A discrete unit comprised of 4 vertexlinked tetrahedra. 2 marks (ii) An infinite 2D layer comprised of edgelinked octahedra 2 marks (iii) A discrete unit

QUESTION 9 Given the data below for the reaction, 2 A 2 B4 C D E 3 F Initial rate, molL.s Initial conc of A, molL Initial conc of B, molL Initial conc of C, molL Experiment 0.1 0.1 0.2 2x 10 3 2. 0.2 0.3 0.2 4 x 103 3. 0.3 0.1 6x 10 3 8 x 103 0.2 4 0.4 0.3 0.6 Calculate the value of k to 3 significant figures.

From the following formula, calculate the amount of each ingredient required to make16 fl oz of lotion. Express all answers in metric system units, and round each final answer to two decimal places. Calamine 35 g Zinc Oxide 0.6 oz Glycerin 15 mL Bentonite Magma 1.5 fl oz Calcium Hydroxide topical solution ad 500 mL (Will give thumbs up)

We wish to study the effect of an uncompetitive inhibitor on an isomerase. the tests are carried out without adding the inhibitor, yielding the following results: subsequently the inhibitor is added, in such a way that the [ES] / [ESI] ratio is 0.25 Calculate: a. Km, Vmax, Apparent Vmax b. Predict how much the initial velocity decreases once the

S (MM) 0,5 3,5 Vo (mMs) 23,5 44

2. 3 pts One of the best known oral antibiotics is pictured below. ante OH a) Redraw the structure filling in all the implied lone pairs and hydrogen atoms. b) Label the hybridization at any 4 carbon atoms. c) Label the ideal bonding geometry at 4 other carbon atoms and at any two heteroatoms. d) Which atoms would NOT actually adopt their ideal