Chemistry Questions and Answers May 06, 2020

What is the value of H of the following chemical reaction? NaOH(aq) + HCl(aq) NaCl(aq) + H2O(l) + 215 kJ

6. 7.8 g of calcium fluoride is dissolved in 100 L of water at 25C. Will a precipitate be formed

Use the AOs as in the energy scale as provided 1) Build the MO diagram for this hypothetical molecule. SHOW YOUR WORK 2) Explain what changed when going from SF6, with no d orbitals involved, to AF6, with d orbitals involved. ,4p ( 4s (a) 3d Six ligand group orbitals (ag AF of Energy FF

"Hello to everyone. I try to calculate the lattice energy of d-fructose using habit 98 and use different radius. i expect to get difference lattice energy and electrostatic interaction for each radius but at the end, i still get the same value of lattice energy and electrostatic interaction tho i use different radius. Does anyone know why ?"

12 An adult patient is treated for hyperthyroidism with exposure to 6.0 Ci of I131 (606 keV B, tun 8.04 days) via ingestion. The thyroid gland is 30.0 g. What is the dose in rad and rem received by the patient over a 15day period

4. The enantiomer shown below is levorotatory. Draw the enantiomer which is dextrorotatory. CH3 H CO2H (R)lactic acid 5. A solution containing 2.0g of compound dissolved in 50ML of solvent generated an observed rotation of planepolarized light (A 589.6nm) of 20 in a polarimeter tube 300mm long at a temperature of 25C. What is the specific

Given the following data for the titration of oxalate (C,0,2) ion with zinc ion, write the titration reaction, and calculate the following Vor 30.50 ml (Ox 0.1350 M (Zn 0.200 M Ksp 2.73 x 10 M a) Balanced Reaction b) Equivalence point volume (Ver) c) pZn 15.00 ml d) pzn Ver e) pzn 24.0 ml

Consider the following reaction NO 10H 8e NH 3H0 PE 14.9 E 0.882 V Calculate pE for a pH of 7 (assuming standard conditions for all other species). Give your answer to one decimal place.

For each reaction between two aqueous solutions described below, use your solubility table to decide if the reaction actually occurs. If the reaction occurs, right the name of the precipitant formed. If the reaction does not occur, write NR (no reaction in the blank) a. aqueous sodium chloride with aqueous calcium nitrate b. aqueous sodium

Mount Rainier in Washington has a height of 4400 m above sea level. Atmospheric pressure decreases with altitude by P Pe 8MhRT , where g is acceleration due to gravity, M is the molar mass of the gas, h is the height above sea level, R is the gas constant, and T is the temperature. The molar mass of dry air is 29.0 gmol and AvapH of water is

Given compound shows which type of isomerism and 1) Chain isomerism 2) Positional isomerism 3) Functional group isomerism 4) Metamerism

63. The most stable conformer of 2methylpropane . CH HCH H H H H H H 1) CH 2) 3) H 4)

64. How many Conformations are possible for nbutane 1) Infinite Total number of benzenoid isomers are possible for C,H,0 2) 7 3) 6 4) 2 65. 1) 2 2) 5 3) 6 4) 7 for this howmany structural isomers are possible when one of the hydrogen is replaced by a chlorine atoms 1) 6 2) 8 3) 4 4) 7

The rate of decomposition of SO, Cl2 according to the reaction so, Cl, (g) SO2 (e) Cl2 (g) can be followed by monitoring the total pressure in the reaction vessel. Consider the following data. Time (s) Total Pressure (torr) 491.7 180.9 548.7 434.0 618.4 605.7 659.1 916.7 721.7 1233.3 773.0 1504.9 809.0 2015.2 860.7 Convert these total pressures

18. Suggest a plausible mechanism with structures of the following reaction CH, CH2B Br, H,0 (CH3),CCHCH, CH H, OH

If an excited hydrogenlike species (ion) emits a radiation of frequency 8.876 x 10 s when the excited electron makes a transition from the first excited state to the ground state, which 16 1 element would this ion correspond to Select one . b. C CN d. Be e. Li

Can someone help me identify the structure of the molecule based on the mass spectrum and the IR spectrum? The mass spectrum can contain the elements C, H, N, O, and halogens. Judging from the IR spectrum, there is a carbonyl group (1750 cm-1) and either an O-H or secondary amine (3600 cm-1) in the molecule. Image caption

100 100 X1 8.9 80 X2 1.1 60 40 0.0 0.0 40 80 120 160 200 mz 1 0.8 0.6F 0.4 0.2 E 3000 2000 1000 Wavenumber (cm1) Relative Transmittance Rel. Intensity 20

How many photons are produced in a laser pulse of 0.897 J at 583 nm

1. You may have observed quite divergent outcomes for the different alkyl halides used. What happened for each alkyl halide? What mechanism won in each system and why? For reference, the alkyl halides used were 1-chlorobutane, 4-chloro-1-butanol, 2-chloro-norbornane, and 2-chloro-2-methylpropane with ether as the solvent and potassium hydroxide,

A volume of 20.0 ml. of 0.500 M NaOH was added to 50.0 ml Of 0.400 M HCI in a coffee cup calorimeter. The temperature of the resulting solution increased by 1.80C. What is the AH of HCI with NaOH Assume that the specific heat of the final solution is 4.184 JigC and the density of both solutions is 1.00 gml. (assume that the calorimeter does not

Draw Walsh diagram for a d ML4 in Ta symmetry undergoing JahnTeller distortion to ML4 Dah symmetry. Include drawings of MOs. Describe the structural distortion you chose and why it is more stable than the undistorted structure.

3. A typical deposit of Quistor, has a mass of 2.50 g. How many molecules of Quistorol are present in this deposit 4. Balance the following chemical reactions a. Z(CIX)2 ZC12 X2 b. R2(C2Y4)3 RC2Y4 CY2 c. ZAY10 X2 ZX2 Y2X 5. Qlime, XY, is produced by the decomposition reaction (the equation is balanced) XCY (s) XY(s) CY(g). What weight of

assuming a person breathes 900 grams of oxygen per day 2. Using the proper chemical equation, how much KCIO, in grams would you need to provide enough oxygen to meet the needs of 1 person for one week

Identical raindrops are dripping from the edge of a roof and hitting the ground below. The raindrops leave the roof in very quick succession at the same frequency, so there are many drops in the air at the same time. What can you say about the center of mass of the raindrops that are in the air between the roof and the ground Neglect air

PROPOSAL FOR THE DESIGN OF A PROCESS TO MANUFACTURE 70,000 TONS OF ACETIC ACID?

Patient Profile Patient is 59 years old with a current weight of 240 pounds BMI is 41 (54tall). She is sedentary (no physical activity whatsoever) and works a desk job. She had a stress test recently and everything was normal. She states that she participated in a walking program last year but had to drop out after 3 weeks because she developed

Care must be taken when diluting sulfuric acid with water because the dilution process is highly exothermic H,0 H,SO, (ag) heat H,SO,() (a) Find AH for diluting 1.00 mol H,SO,) (d 1.83 gmL) to 1 L of 1.00 M H,SO,(ag) (d1.060 gmL). kJ (b) Suppose you carry out the dilution in a calorimeter. The initial Tis 25.7C, and the specific heat capacity of

Draw the structure of the cerebroside containing BDglucopyranose and palmitoleic acid.

When 15.0 mL of a 8.06x104 M nickel(II) nitrate solution is combined with 12.0 mL of a 2.80x104 M ammonium sulfide solution does a precipitate form (yes or no) For these conditions the Reaction Quotient, Q, is equal to

When a 45.50 mL solution of 0.235 M of NazP was mixed with a 35.80 mL solution of 0.325 M Cd(NO3)2, a precipitate was formed. The mass of the precipitate was 1.332 g Draw a molecular level diagram of Na3P solution.

give me answer fast please

Q1 With the help of external references (textbook, internet), draw the reaction mechanism of the saponification of methyl salicylate to form salicylic acid. Make sure you clearly indicate arrow pushing. 1. aq. NaOH OCH3 OH 2. H,SO4 OH HO

OCH CHO 76 and are 1) Positional isomers 2) Functional isomers 3) Chain isomers 4) Ring chain isomers How many cyclic isomers of C,H,, are possible 1) 2 2) 3 3) 4 4) 5

Which of the following are correct for metamers 1) Secondary amines shows metamerism 2) Metamers having same functional group 3) Secondary amides shows metamerism 4) All are correct Number of primary amines of the formula C,H,,N is 74. 1) 1 2) 2 3) 3 4) 4 FOCH CH

71. Which of the following plots are correct for potential energy of butane as a function about C, C, bond E E 6 120 180 240 300 360 180 120 6 60 120 18 1) 2) E 120 180 240 300 360 3) 4) All are correct

Many proteases are produced as longer precursors, they are activated randomly, and the likeliness of activation increases when they reach the location of the action. True/false

For the reaction, A3 2e A (E 0.500 V vs. NHE), the iV curve for a solution containing 2.00 mM A and 1.00 mM A in an electrolyte shows ie 4.00 u A and ia 2.40 I A. (a) What is E12 (b) Sketch the expected iV curve. 3

freezing point v) 0.5 molar Naon salutim having is 299 k wwhen it is dissolved in ethanol with freezing point is . its 300k. What is ATF

Consult the literature and come up with a reaction scheme for 1,1ditertbutyl ferrocene starting from 1.5 grams of 6,6dimethylfulvene. Suggest a modified experimental procedure that will fit into a 3 hour lab period and write it in proper experimental format. In a separate paragraph, note any important safety concerns with your prep and include

Calculate the value of KI in the presence of 0.22 mM inhibitor. a=1+ (I) / K i

a) Explain what properties of carbohydrates the barfoeds, seliwanoffs, and bials tests test for. b) Draw the structures of maltose and lactose c) What monosaccharides are these composed of d) Could these three chemical tests determine if an unknown is comprised of maltose or lactose Why or why not

In an organic lab experiment, Hinsberg Test for Amines was done . To the unknown 10% of aq KOH was added. Then benzenesulfonyl chloride was added. Then it was warmed and then cooled. There were two layers. They were Separated. To the organic layer 5% HCL was added and it was INSOLUBLE. to the aqueous layer 5% HCL was added until it got to pH4 and

For the reaction shown, find the limiting reactant for each of the following initial amounts of reactants. 2 Al (s) 3 Cl, (G) 2 AICI, (s) Part A 1.0 g Al 1.0 g Cla Express your answer as a chemical formula. AE

A. A 45.0 g sample of ammonia was decomposed using a catalytic process producing hydrogen gas and nitrogen gas. Write the balanced equation for the process and calculate the volume of each gas produced (at STP). Explain any relationship you may observe between the volumes obtained and the balanced equation of the process.

8. Predict the product(s) of the bromination of cis3hexene. Brg Br H Br Br Br Br H. Br Br H Br Br H. H. Br A Br D

The active site of the serine protease chymotrypsin is shown schematically below. i) Use curly arrows to show how the enzyme achieves cleavage of the amide bond. ii) The histidine side chain contains imidazole. Is imidazole aromatic? Explain your reasoning.

Asp (His) HN (Ser EN EN HO R N R I.

structure of the major organic product isolated from the reaction of 1-hexyne with Hydrogen chloride (1 mol)

Draw a tautomer of each of the two compounds below. Draw tautomeric forms of the following compounds:

Z Z

Using curly arrows, draw a mechanism for its formation. Draw the product of the following reaction & Draw a mechanism for its formation using curly arrows Draw out the expected product and suggest a mechanism for its formation using curly arrows:

Z

1.Draw two tautomeric forms of Thymine 2. Give mechanisms for the following conversions 3.Suggest a synthesis for the following heterocycle

NH N

1. Suggest a synthesis for the following heterocycle and provide a mechanism 2. For your heterocycle above, suggest reaction conditions and a mechanism for the removal of the CN group

CEN

A key step in Coreys synthesis of the potent anti-cancer agent Ecteinascidin 743 is shown below. Give a mechanism.

OBn OBn .. BF3.OEt, HN. 3 Molecular sieves OBn H OBn

The indole derivative shown below is labeled with tritium in the position shown. When it is cyclised with the Lewis acid boron trifluoride, the label may be found with equal probability in the two places shown. Provide a mechanism for this reaction that accounts for this observation.

(5050) BF3 H H H. 3.

Zolpidem is a hypnotic drug acting on the GABA receptor complex, but which has a non-benzodiazepine pharmacophore. It may be synthesized as follows: i) Give a mechanism for the first step ii) Give a mechanism for the Mannich step iii) Give a mechanism for the Hofmann Elimination and subsequent attack of cyanide iv) Provide a mechanism for the

NH2 MeNH2, ACOH ELOH, A CH2O Br i) Mel i) NaCN DIC, HOBT, HNMe2 HCI (32 vv in H20) 180C NC OH

Provide the structure of Lysine at physiological pH? provide all working for this problem

The solubility of Barium hydroxide at 25oC is 1.85 g/100 mL solution. a. What is the Ksp of barium hydroxide at 25oC? (4 pts) b. How would the addition of 0.100 M BaCl2 affect the solubility of Barium hydroxide? Briefly explain your answer. (3 pts) c. How would the addition of HCl affect the solubility of Barium hydroxide? Briefly explain your

A buffer solution contains 0.304 M C,HNH,Br and 0.370 M C,H5NH, (aniline). Determine the pH change when 0.095 mol HBr is added to 1.00 L of the buffer. pH after addition pH before addition pH change A buffer solution contains 0.375 M KH,PO, and 0.253 M K,HPO4. Determine the pH change when 0.090 mol NaOH is added to 1.00 L of the buffer. pH

Draw a viable mechanism for its formation from the starting materials

EtO,C EtO2C CO2Et x2 NH3 H.

i need full chemical reactions of the following: (must include structures) 1) CHO + K 2 HPO 4 --> 2) acetylsalicylic acid product of 1) + HCl --> 3) caffeine + NaCl --> 4) paracemtol + acetone -->

Q5 lon Chromatography A 20 L sample solution, containing approximately 3 mM sodium nitrate and 2 mM calcium sulfate in water, was injected into an anion exchange chromatograph and eluted with 8.0 mM KOH at a flow of 1.2 mLmin. The column had a capacity of 30 ueq and void volume of 2.0 mL. The system and resulting chromatograph is shown below. a)

A solution contains 22 (w of lithium citrate. What is the concentration, in mEg, of lithium ion in the solution. The malecular weight of ithium citrate, Li 3(C H 50 7)H 20, is 282 and the atomic weight of LI is 7. Selected Answer O (None Given) Correct Answer O 234.04 5

Provide a mechanism of below reaction using curly arrows

NH2 N. HN Br NH3

3. Draw the MAJOR product(s) of the following reactions. Show stereochemistry when appropriate. If no reaction is predicted, write NO REACTION. Circle the appropriate mechanism for each reaction. 20 Points NaSH SN1 SN2 E1 E2 Br NASH SN1 Sy2 E1 E2 Br KOtBu SN1 SN2 E1 E2 Br NaOH SN1 SN2 E1 E2

2. Determine the geometry of the alkene products of the following E2 reactions under each of the guided samples A. When the a C is a chiral center but BC is not a chiral center Br NaOH B. When the BC is a chiral center but a C is not a chiral center NaOtBu Br C. When both a BCs are not chiral NaH D. When E2 occurs in a ring OMs NaH E. When both

Predict the geometry of the following E2 products

Br NaOH ..... Br NaOEt Et KH I

2. Why are some enzymes needed only in the gluconeogenesis pathway and not in the glycolysis pathway 3. Which one of the following reactions only occurs during gluconeogenesis (i.e., not during glycolysis) a. 1,3bisphosphglycerate into 3phosphoglycerate b. Glucose 6phosphate into fructose 6phosphate c. Oxaloacetate into Phosphoenolpyruvate d.

5. A high school girl who is selfconscious about her appearance has been fasting for several days to fit into a dress she intentionally bought a size too small for a school dance. Which of her organstissues is producing the glucose that is being synthesized through gluconeogenesis a. Red blood cells b. Muscles c. Liver d. Brain

4. An increase in glucagon levels can a. Promote the degradation of glycogen (i.e., glycogenolysis) b. Occurs during the fasting state (starvation) c. Promotes the synthesis of glycogen d. A and B

3. Which one of the following reactions only occurs during gluconeogenesis (i.e., not during glycolysis) a. 1,3bisphosphglycerate into 3phosphoglycerate b. Glucose 6phosphate into fructose 6phosphate c. Oxaloacetate into Phosphoenolpyruvate d. Phosphoenolpyruvate into Pyruvate

What is the pH of a solution if the concentration of H 3 O + is 0.366

Jasmone is a valuable material in the perfume industry and used in many soaps and cosmetics. Suppose we are recovering this material from a water suspension of jasmine flowers by an extraction with benzene. The local mass transfer coefficient for jasmone in benzene is 3.0 x 104 cms. The local mass transfer coefficient of jasmone in the water is

A titration was done on a 25.00 mL aliquot of Ca(OH),. The endpoint of the 3.00 M HCI solution occurred at 28.35 mL. What was the Molarity concentration of the aliquot of NaOH Molarity of the aliquot of NaOH NaOH M

Looking at a table of electrochemical potentials, what would the window of potential be for: Pt to be an ideally polarizable electrode in an aqueous solution of pH 12? Pt to be an ideally polarizable electrode in an aqueous solution of pH 2?

Provide the mechanism by using curly arrows

H NH2 N. HN Br NH3

Total number of monochloro products formed for methyl cyclohexane are 'x' and the total number of distillates obtained upon fractional distillation are 'y' then (x-y) is n

Determine the absolute configurations of the labeled carbons (a and b) (a) a Rb R (c) a Sb R (b) a Rb S (d) a Sb S

What compound is represented by the Newman projection shown CH, H,C CH, H (A) CH,CH,CH, (c) CH,CHCH), (B) (CH,CHCHCH, (D) CH,CH CH,CHCH

K Equlibrium constant is maximum for (A)Me (B)Et (C) (D)

2. For each of the following substances, compute the final temperature when sensible heat in the amount of 3 kJ mol is added to the subcooled liquid at 25C and atmospheric pressure. (a) methanol (b) ethanol (c) benzene (d) toluene (e) water For each case, use the trial and error iterative method or the goal seek method from Excel

What is the mole fraction of toluene in a solution of 3.4 mol of benzene and 5.2 mol of toluene A) 0.64 B) 0.54. C) 0.60. D) 0.24. E). 0.40

Which of the following is always produced as a result of an energy conversion process A) heat B) light C) electrical polarization D) gamma rays E) sound

Select the coefficents to balance the reaction Mg HCl MgCl, H2 O 2,1,2,1 O 2.2.1.1 O 1.2,1.1 O1.1.2.2

Excessive carbohydrate intake results in the synthesis of lipids in mammals. Discuss this statement using specific examples from your text books.

What is the final temperature in degree C when 10.00 grams of Calcium chloride are dissolved in 100.00 grams of H20 Heat of solution for Calcium chloride is 81.3 kJ mole. (negative 81.3) The initial temperature of the water and the Calcium chloride are both 25.0 C. Assume the specific heat of the solution is the same as the specific heat of pure

The bond energies (Jbond) for A and B pairs and the heat of mixing expression are estimated to be CAA 6.5 x 1020 eBB 5.3 x 1020 5.4 x 1020 AHmix XAXB(7500XA 18200XB) e AB Compute and plot the fractions of AA, AB and BB bonds in the system as a func tion of composition.

True or False The ideal dilute solution model describes a solution in which both the solute (A) and solvent (B) obey Raoults Law as XA 0 and XB 1. (Circle your answer) a. True b. False (3 Points) True or False It is possible to dissolve enough solute into a solvent, while keeping the solvent the majority compound, to result in a solution with a

Explain the diastereomeric outcome of the following reactions with reference to transition state model diagrams

OH OH NABH4 N H, H,O N OH OH DBAI N H, H2O N D.. O..

Molarity (M) of standarded HCI 10348 Cost () per gam Cost (5ipet 00221 gram Tms makes of HC cies of OH reacting with provided by antacid Tablet identny Turms(T) 10 Trial Rolaids R) 11 A11 Rolaids R) 12 A12 Rolaids R) 13 A13 Rolaids( R) 14 A21 Rolaids( R) 15 A22 Rolaids R) 16 A23 Rolaidst R) 17 A31 Rolaidst R) 18 A32 Rolaids R) 19 A3.3 Rolaids R)

Explain why two different reducing agents give diastereomeric products.

OH NABH4 Under FelkinAnh control H, H20 Me DBAI Under chelation control H, H20 Me DBAI

Draw the mechanism for the following reaction. Br Br Me. TICI4 HN.

Suggest structures for compounds Aand B. Explain with referenceto transition state models which isomer of compound Bis formed. Explain with references to transition state (ZimmermanTraxler) diagrams the stereochemical outcome of the aldol reaction. ,Me,SICI A LDA NaH Ph TMSO Me synaldol

NH,NO3Cag) NH, (ag) N0, (aq) AH 25.7 kJ 3D 1. Consider the reaction above. In this reaction, heat is a (B reaction. This reaction is said be D) (AL Therefore, this by enthalpy. that can be purchased at is an 2. This reaction probably can be used to make your local pharmacy store. 3. Comparing the reactants and products of this reaction, you can

2021. Standard addition. To measure Ca in breakfast cereal, 0.521 6 g of crushed Cheerios was ashed in a crucible at 600C in air for 2 h.32 The residue was dissolved in 6 M HCl, quantitatively transferred to a volumetric flask, and diluted to 100.0 mL. Then 5.00mL aliquots were transferred to 50mL volumetric flasks. Each was treated with standard

()-Berkeleyamide D is a natural product from Penicillium rubrum bacteria which is a micromolar inhibitor of the potential drug target MMP-3. This following synthetic sequence is adapted from a recently reported biomimetic synthesis. a) Propose reagents and their order for steps i) and ii) to convert 8 into 9. (2 Marks) b) Redraw step iv) in the

Ph NH OH H (2)berkeleyamide D

Give a mechanism for Step 1 by using curly arrows. (5 marks)

cat. HCI H. HN NH2 in EIOH, heat Step 1 POCI, heat Step 2 HyPdC in EOH Step 3

5. Calculate the overvoltage (in V) that is needed to sustain a current density of 20 mAcm at a Pt Fe, Fe clectrode at 25 C. Take jo 2.5 x 10 Acm and a 0.58. (Hint The overvoltage, n, is a very large positive value