Chemistry Questions and Answers May 12, 2020

What is undergoing reduction in the redox reaction represented by the following cell notation Pb(s) Pb (aq) Il H(aq) H(g) Pt(s) Halal H(aq) PO Pag POR

Which of the following is an enamine L NCH IV. II. NCH, V. CH3 III OV III 11 IV CH3 OH CH3 NNH NN O

1. HO H For the following products draw in the correct two reagents using molecules from the above nine molecules. Add H20 as a product if needed. oto

An iron ring has a X-section of 3 cm 2 and a mean diameter of 25 cm. An air-gap of 0.4 mm has been cut across the section of the ring. The ring is wound with a coil of 200 turns through which a current of 2 A is passed. If the total magnetic flux is 0.24 mWb, find the relative permeability of iron, assuming no magnetic leakage.

Complete the given reaction:

H30 Eto OEt

For the reaction 3 Fe(s) 4 H20(g) Fe3O4(s) 4 H2(g) write the expression for Kc in terms of Kp O Kc x O Kc Kp O Kc K,RT 3D Kc Kp RT

Is glitter polar or nonpolar? How can you tell? Is food coloring polar or nonpolar? How can you tell? and draw the structure and more in detail.

In the reaction 2A 3B C, how many units of C form when 10 units of A react 3 10 Question 2 In the reaction 2 Al 3 Cl, 2 AICI, how many moles of Cl gas are needed to react with 30 moles of aluminum 45 3 30

Balance the following equationHBr Ba(OH)2BaBr HO 2.1.1.2 11.1.1 2.1.2.1 1.2.21

Draw the product Et2Cu

At 25 deg C, 0.10M ammonium chloride has been added to 0.05M ammonia. Determine the pH of the solution and the percent ionization. (Buffer sol: 100 mL)

At 25 deg C, 0.10M ammonium chloride has been added to 0.05M ammonia. Determine the following : A. The pH of the solutio* B. The percentage ionizatio* Your answer C. What will happen to the ph of the solution upon adding: a) 25 mL of 0.1M NaOH b) 25 mL of 0.10M NaOH

Which is the Haworth projection for the 8anomer of the straight sugar shown below CHO H OH HO HO H H OH CH,OH b. CHOH H O OH CHOH HO OH OH H OH H OH ld. OLOH HO CHOH H HO OH OH

3. Explain why NH2 is capable of deprotonating a terminal alkyne but OH is not.

4. Draw the mechanism for the following reaction and name the product Na NH3 (1)

An excess amount of silver nitrate was added to 2.50 grams of impure barium chloride which resulted to a silver chloride precipitate. A. What is the mass of the precipitate formed B. What is the percentage barium chloride in the sample

Suppose the below reaction in the forward direction is first order in A and the rate constant is 1.30x10s1 The reverse reaction is first order in Band the rate constant is 4.10x102s1 at the same temperature. 1st attempt What is the value of the equilibrium constant for the below reaction at this temperature A B K

An element has 4 electrons in the valence shell that is designated as L what is the name of the element. Write the electronic configuration and noble gas notation for this element.

An element has 4 electrons in the valence shell that is designated as L what is the name of the element. Write the electronic configuration and noble gas notation for this element.

Which compound inhibits the entry of fatty acyl CoA into the mitochondria when the cell is in the highenergy state mitochondrial malonyl CoA carnitine acyltransferase I acetyl CoA carboxylase 2 citrate cytosolic malonyl CoA

Determine the stabilization energy of compound A and B based on 1) Set up the Hckel and matrix for both compounds as well as the eigenvalues 2) determine the energy of the system as stabilization energy (in Hckelunits B)

How to synthesize from left to right?

OH H. A 2. OH

For each of the following, identify the product(s) that would be formed through the indicated sequence of steps from the given starting material.

(1) HNO H,SO, (2) Fe, HCI HO CI (3) AcCI, (CHCH2N (4) SnBu, Pd(Ph,P). base

For each of the following, identify the product(s) that would be formed through the indicated sequence of steps from the given starting material.

(1) O (2) Me,S (3) H,CPPh, (excess) (4) Pd(Ph,P), Br. Ph (excess), base

For each of the following, identify the product(s) that would be formed through the indicated sequence of steps from the given starting material.

(1) Br, (2) NaNH, (3 equiv.), A, H,O (3) Br Cul, Pd(Ph,P) Et NH

For each of the following, identify the product(s) that would be formed through the indicated sequence of steps from the given starting material.

(1) LDA NBS (2) tBUOK, tBUOH (3) Grubbs II (4) EtMgBr (ess) H,O

Complete the following:

(1) O (2) Me,S (3) H,CPPh, (excess) (4) Pd(Ph,P), Br. Ph (excess), base

Complete the following:

(1) Br, (2) NaNH, (3 equiv.), A, H,O (3) Br Cul, Pd(Ph,P) Et NH

(1) LDA NBS (2) tBUOK, tBUOH (3) Grubbs II (4) EtMgBr (ess) H,O

Fill in the table according the given requirement. Molecule Lewis Structure Electronic Shape Molecule shape Polar molecule? (yes/no) H 2 O SOCl 2 CO HNO 3 N 2 H 2 OCN CH 3 (CH 2 ) 4 CH 3

1. Use valence bond theory to write a hybridization and bonding scheme for the carbon dioxide molecule.

2. Draw the molecular orbital diagram for N 2 . What is the bond order of this molecule?

In step 4 of glycolysis, F16BP is converted to GAP and DHAP. In the mechanism carried out by the aldolase (the enzyme the carries out this reaction) an active site lysine residue reacts with the substrates carbonyl group to form a Schiff base. Briefly, what is the logic behind the formation of the Schiff base (i.e. why is it beneficial that the

Reaction Mixture I. BrOs o H. Temp. Time Rate 1 0.0020 0.008 0.02 19.0 C 182 sec 4e5 2 0.0040 0.008 0.02 19.0 C 83 sec 4.65 3 0.0020 0.016 0.02 19.0 C 90 sec 1.7e4 4 .0020 0.008 0.04 19.0 C 46 sec 1.9e4 0.0016 0.004 0.03 19.0 C 228 sec 2.65 The following table shows the time data run at different temperatures as described in Step 5 of the

Rank the following, strongest acid first (ex ABCDE where A is the strongest acid) H LOCH H NO H OH 5 CHO

Predict what the NMR spectrum would look like for each compound. You dont have to say what the specific frequency of each signal is. Circle and label each set of Hydrogen atoms and state what the integral and splitting pattern would be for each group. NH2

In order to determine the rate of photosynthesis (the conversion by plants of carbon dioxide and water into glucose and oxygen), the oxygen gas emitted by an aquatic plant is collected over water at a temperature of 293 K and a total pressure of 757.0 mmHg. Over a specific timeperiod, a total of 1.08 L of gas is collected. The partial pressure of

7. Estimate the boiling point order by typing an appropriate number in the box below each name. OH NH2 HO. 2aminobutane N,Ndimethylethylamine 2butanol Nmethylis opropylamine 2methylbutane propanoic acid 2butanone 2methoxyprop ane ,11. Naproxen is a nonsteroidal antiinflammatory drug (NSAID). It is often sold as its sodium salt, naproxen sodium.

14. Based on their structures, rank phenol, benzene, benzaldehyde, and benzoic acid in terms of lowest to highest boiling point. COH H. 15. Is squaric acid soluble in water Explain your reasoning. OH HO, 16. Consider the molecular structures of propionic acid (CH3CHCOOH) and methyl acetate (CHCOOCH3). a) Which substance has a high boiling point

12. Various methods are employed in order to remove the caffeine from coffee beans to make decaffeinated or decaf coffee. Some older methods used organic solvents like dichloromethane or chloroform. A solvent which is still sometimes used is water, but now a common method is extraction by carbon dioxide as a supercritical fluid. When using the

Rank the volatility of the following in water from lowest to highest. CH3 CH,CCH, CH neopentane 2methylbutan2ol 2,3dimethylbutane pentan1ol hexane 9. Which intermolecular forces would you expect to occur between two molecules of cholesterol Which portions of the molecule will interact with each other through these intermolecular forces 10. DNA

Rank the following in terms of increasing boiling point LICI C3H,OH CAHg Which is higher boiling, and why (Both have the same formula, C3HgO) CH3CH2OCH3 CH3CH2CH2OH Rank the melting points for the following, 1 being highest Ca(OH)2 CH3CH2CH2OH CH3CH2CH2CH2OH CH3CHOCH3 Which of the following correctly orders the boiling point of benzaldehyde,

24. Determine which proton is more acidic using resonance arguments. H N H ,25. Indicate the order of base strength of these compounds by ranking 14 (1 being the strongest base) A) NH NCH3 O,N NH2 NH2 B) NH ON NH2 C) NH NH NH D) NH NH

19. Rank in terms of decreasing acidity HO. 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 HOCF3 (11) HO. H. ,22. Heartburn is caused by a buildup of

18. Rank these compounds in terms of increasing acidity HNO, H,SO4 HF H,CO3 . NH3 CH4 H2O HCI b. OH NH2 HO . HF LOH2 d. 47 ,17. For each set of common laboratory solvents, identify the compound that is more acidic. H3C CH3 methanol acetone vs. CI HCCI H dichloromethane hexane vs. H ethyl acetate water vs. 18. Rank these compounds in terms of

What is the stronger acid in the following reaction if the equilibrium constant is much less than 0.01 HNO3 H,SO4 H,O3 HS04 a) b) c) d) 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

equate the followng equations a) Na, SO, (KIC(x) Naz SCK) Colg) b)HCIG) Ozlg) e)PCIsle) H20(5) H20(5) C2lg) H3 POulog) HCICog) d Iritrogen monolde ok ygen eleton ((2H6) oxygen nitrogen dioxde Corbondioxide twater 2 fe (k)3C l2 (g)2fe Clg(L) (2 How many moles of feCla are obtained when an excesslve amount of fe is reacted with 7,26 moles of Cl2

Draw and discuss the potential contributions to hydrophobic and van der Waals interactions and ionic and hydrogen bonds for the side chains of Glu, Ile, Ser, and Trp in a protein.

4. Synthesis of the following polymers a). PS(Mn10000)b1,4PB(Mn20000)bPS(Mn50000) b). PS(Mn10000)bPolyethylene(Mn20000) c). Polyethylene (Mn10000)altpropylene(Mn20000) d). 4arm star PS (Mn40000)

14. Calculate AG for the reaction catalyzed by Na, K ATPase that expels 3 Na outside in exchange for 2 K coming inside. Assume actual AG for ATP hydrolysis 50 kJmol, membrane potential on the cell membrane 70 mV (negative inside), K 140 mM in, 4 mM out, Na 12 mM in, 145 mM out, temperature is 37C.

What is the standard free energy change for the following reaction at 25C CH4(g) 2 02(g) CO2(g) 2 H20() OA. 818.0 kJ O B. 739.6 k) OC 614.9 k) OD. O D. 923.7 kj

Calculate the equilibrium concentrations of the gases in the reaction C (s) H20 (g) CO(g) H2 (g) Kp 2.44 3D If a vessel is initially filled with 1.20 atm H2O.

3. When A is treated with Pd(PPh)4 in the presence of methyl acrylate, B is formed. When C is treated with Pd(PPh)4 in the presence of methyl acrylate, D is formed. Provide a mechanism for each reaction and explain the difference in the reaction pathways. CO,Me Br Pd(PPh,)4 EtN CO,Me methyl acrylate A Br Pd(PPh,). EtN CO,Me methyl acrylate

The PEC diagram for the dissolution of the mineral chalcocite (Cu2S) in water is shown to the right. What is true about the ions that make up this mineral E, 2Cu(aq) S2(aq) M Cu,S(s) UM of Config The mineral is soluble but becomes slightly less soluble at high T The mineral is soluble only at high temperatures O The mineral is soluble only at

Bovine ATP synthase complex contains 8 csubunits while yeast ATP synthase contains 10 csubunits. If NADH is oxidized via the electron transport chain, which organisms ATP synthase complex will produce more ATP from the NADH oxidation Support your answer using chemical details.

Draw the complete and correct way arrow-push mechanism using the reagent in the first step to turn limonene into bromohydrine. Also, please help me draw the complete and correct way arrow-push mechanism using the reagent in the second step to turn bromohydrine into limonene oxide. Please explain afterwards. Thank you so much. PS. If you can

Br NBS N2OH AcetoneH,O limonene bromohydrine limonene oxide

4. Rationalize the methyl group arrangement in euphol compared to other triterpenes.

In this lab, it passes the halogen test with white ppt and bromine/ch2cl2 test that led to stay a red solution ( which proved that it may have Pantene) and the liquid is from group X.

1. Treatment of a 0.2500-gram sample of impure potassium chloride with an excess of AgNO3resulted in the formation of 0.2912 g of AgCl. Calculate the percentage of KCl in the sample. 2. The aluminum in a 0.910-gram sample of impure ammonium aluminum sulfate was precipitated with aqueous ammonia as the hydrous Al2O3 H2O. The precipitate was

1. What mass of Cu(IO3) can be formed from 0.500 gram CuSO4 5H2O? 2. What mass of KIO3 is needed to convert the copper in 0.200 gram in CuSO4 5H2O to Cu(IO3)2? 3. What mass of AgI can be produced from a 0.512 gram sample that assays 20.1% AlI3?

1. Precipitate used in the gravimetric determination of uranium include Na2U2O7 (634.0 g/mol), (UO2)2P2O7 (714.0 g/mol), and V2O5-2UO3 (753.9 g/mol). Which of these weighing forms provides the greatest mass of the precipitate from a given quantity of uranium? 2. A 0.2121-gram sample of organic compound was burned in a stream of oxygen and the CO2

1. Ammoniacal nitrogen can be determined by treatment of the sample with chloroplatinic acid; the product is slightly soluble ammonium chloride palatinate H2PtCl6 + 2NH4 + (NH4)2PtCl6 + 2H+ The precipitate decomposes on ignition, yielding metallic platinum and gaseous products: (NH4)2PtCl6 Pt(s) + 2Cl2 (g) + 2NH3 (g) + 2HCl Calculate the

Rank the volatility of the following in water from lowest to highest. CH3 OH CH,CCH, CH 2methylbutan2ol 2,3dimethylbutane neopentane heane pentan1ol

2. Propose a synthesis of the following compound using the starting material given below.

Suppose that a linear Na 26 molecule could be formed by combining the 3s orbitals on each atom into delocalized MOs. How many nodal planes are in the highest occupied molecular orbital (HOMO) of this molecule?

10. What is the product of the following reaction Pd(0) OAC Me Me ONa Me Me E Me F

9. What TWO starting material would lead to the product shown Br OH Me,Sn Pa(0)

STANDARDIZATION OF ca 0.02M KMnO4 SOLUTION WITH STANDARD OXALIC ACID. REQUIREMENTS (1) KMnO4 solution (0,02M) (2) Oxalic acid 0.05M (3) 3M H2SO4 solution The oxalic acid dihydrate solution was prepared by weighing out accurately an appropriate mass of the solid, transferred it to a 250 cm3 volumetric flask, and made up to the mark with distilled

3. (15 pts) Perform a retrosynthetic analysis on the following peptide from the given starting materials. 5. T 1. 2. 3. 4. HN N. 6. 7. H, PdC, EtOH 8. 5. 11 HO 1. 2. 3. 4.

Predict the products and indicate the relative stereochemistry for the following transformations. When necessary indicate the major product

of 1. Me 2. NaH, DMF CI, py, CH2CI2 Br OEt NH2 3. H20, H, heat 4. Cp2LaNMe2, PhH

Predict the products and indicate the relative stereochemistry for the following transformations. When necessary indicate the major product

1. mC, H2Clz 2. ., Pr 3. NalO4 4. H2N Pr

Draw the organic product of the following reaction. Draw all atoms. Select Draw Rings More C H CI HCI HCCE CCH H.

HNO, 2CI0, HNO, 2CI0, H,0 ,For the above redox reaction, assign oxidation numbers and use them to identify the element oxidized and the element reduced. name of the element oxidized name of the clement reduced

Measured bond angle VSEPR Idealized bond angle CCC. HCC (center C is the middle C in the structure) (1pts) 9c. Are these results for C CC structure consistent with what you observed in Avogadro (within a few degrees) Explain briefly. Savod Normal BIIU Te Table view List view 10a. Change one of the CC bonds to a double bond. CCC structure Lone

H H What is the hybridization around the carbon atom in the drawing CC below H H a sp sp2 sp3 C.

A compound with a retention time of 465.7 has a width at half height of 8.8 on a column 17.3 meter long. Calculate the helght of a theoretical plate in mm Select one Oa. 1,113 Ob.0,126 Oc.0.039 Od. 0,111 Oe, 0.386 of the analyte increases, As the temperature of a gas chromatography column increases, the the retention time and the peak shape Select

(3) A 0.35 mm diameter open tubular gas chromatography column is coated with stationary phase that is 0.25 im thick. The diffusion coefficient for a compound with a retention factor k 10 is D 1.5x10 m2s in the gas phase and D 2.5x10 m s in the stationary phase. Calculate the plate height if the linear flow rate is 20 cm s. If you increase the

An electron in the n 8 level of a C ion emits a photon of wavelength 104 nm. Hz (a) What is the frequency of this photon in Hertz (answer in 3 sig.figs.) (b) What is the energy of this photon in Joules (answer in 3 sig.figs.) (c) Would you expect the electron to move to a higher or lower energy level (d) To what energy level does the electron

Calculate the formation heat of Pb0 at 800 K. Given Chemical reaction for the formation of Pbo Pb (1) 0 2(g) Pb0 (s)

Fe 20 3(s) 3H 2(g) For the reaction above, calculate the standard Gibbs Free energy change at 700 K. 2Fe (s) 3H 20 (g)

Thiamine-catalyzed reactions Draw mechanisms for reactions above (enzyme is inactivated by the mechanism-based inhibitor)

cys .S. H. Ecys. cys CO 2

Mention whether the compound is soluble or not:

HCCH,NHCH,CH3 O soluble O nsoluble

Name the given compound with its nomenclature.

Mention whether the compound is soluble or not:

NH2 O soluble O insoluble

Mention whether the compound is soluble or not:

NH, CH, CHCH, CH, O soluble O insoluble

Identify the main product of the following chemical reactions. If no reaction occurs, write N.R a) 140C H CH3 KMNO, Excess b) HO. OH c) 180C CH3 H

Identify the main product of the following chemical reactions. If no reaction occurs, write N.R OH 180C CH3 H CH3 (0 CH3 CH KMNO,

What is the major product of the following reaction Hz. Lindlar cat OA OB. OC D.

Of the following molecules, which most readily undergpes a bimclecular elimim Br Br A ,Br Br Br D E

Provide a detailed step by step mechanism for this. Please show all arrows and electrons.

H,C. .CH3 CH, HN NH3 H,C H3

A voltaic electrochemical cell is set up using the following two halfcell reactions. Compute the cell potential. Zn(s) Zn2(aq, 4.55 M) 2 e NO3 (aq, 0.22 M) 4 H(aq, 1.00 M) 3 e NO(g, 3.888 M) 2 H2O(1)

Caveolin is a bulky membrane protein commonly found in many membrane rafts. Caveolin is found exclusively in the inner leaflet. With its large size and bulk, caveolin takes up a lot of space in the inner leaflet. What effect might you expect to see if several caveolin proteins are found in a small area (such as a membrane raft) Hint Remember that

Which of the following DielsAlder reactions would be fastest DielsAlder CHO OCH3 DielsAlder DielsAlder OCH3 CHO DielsAlder

Run the widget below to generate a carbon species plot like the one found on page 431 of your text book to answer the following questions. The tempC control allows you to change the temperature of the system in degrees Celsius. In 2 from chm210 4 import CarbonDiagraml w interactive (CarbonDiagraml, tempC (50, 50)) display (w) tempC 25 1.0 0.8 0.6

and best indicate degree of polarity, of ions and water solubility Mobile phase and stationary phase Dipole moment and dielectric constant Dipole moment and of ions

Phosphofructokinase1 (PFK1) catalyzes the transfer of a phosphoryl group from ATP to fructose 6phosphate. Shown is a graph of the rate of PFK1 vs. ATP). Concisely explain the shape of the graph. 2 (ATP) (mmol l) PFK1 reaction rate

A 19.00 kg sample of an unknown compound contains 0.06 kg of hydrogen, 11.01 kg of gold, 7.93 kg of chlorine. Determine the percentage composition of the compound.

If 0.35mL of methyl benzoate react with 0.26mL of nitric acid and 0.55mL of sulfuric acid, then how many moles of Methyl -3- nitrobenzoate are obtained?

1. Hg(OAc)2, H20 2. NaBH4