The suns energy comes from a. nuclear fission b. radioactivity c. the conversion of hydrogen to helium d. the conversion of helium to hydrogen

Hamming codes are used for error detection and correction in communication and memory systems. Error detection and correction capability is incorporated in these codes by inserting extra bits into...

For each synthesis proposed in Problem 44 that is not likely to give a good yield of ether product, suggest an alternative synthesis beginning with suitable alcohols or haloalkanes that will give a...

Determine the molecular formulas corresponding to each of the following structures. For each structure, calculate the number of degrees of unsaturation from the molecular formula and evaluate whether...

Predict the spin spin splitting that you would expect to observe in the NMR spectra of each compound in Problem 36. (Reminder: Hydrogens attached to oxygen and nitrogen do not normally exhibit spin ...

Give the product of addition to Br 2 to each alkene in Problem 37. Pay attention to stereochemistry. In Problem 37 Give the expected major product from the reaction of each alkene with (i)...

Predict the 13 C NMR spectra of the compounds in Problem 36, with and without proton decoupling. CH3 CH3 () ,CI CH,CI (a) CH;CH,CH,CH; (b) CH;CHCH3 (d) CH;CHCH,CH3 Br H3 CH3 H,C-CH, () ,CNH, (f)...

Give the reagents and conditions necessary for each of the following transformations and comment on the thermodynamics of each (a) cyclohexanol cyclohexene; (b) cyclohexene cyclohexanol; (c)...

The IR spectrum of 1,8-nonadiyne displays a strong, sharp band at 3300 cm -1 . What is the origin of this absorption? Treatment of 1,8-nonadiyne with NaNH 2 , then with D 2 O, leads to the...

Which of the following methods is best suited as a high-yield synthesis of 2-methyl 3-hexyne, CI CI H.. Lindlar's catalyst NANH, liquid NH, (a) (b) 1. Cl,, CCI, 2. NANH,, liquid NH, -Li + (c) (d) Br...

Give the expected major product of the reaction of propyne with each of the following reagents. (a) D 2 , Pd CaCO 3 , Pb(O 2 CCH 3 ) 2 , quinoline; (b) Na, ND 3 ; (c) 1 equivalent HI; (d) 2...

Propose several syntheses of cis-3-heptene, beginning with each of the following molecules. Note in each case whether your proposed route gives the desired compound as a major or minor final product....

Rank the following six molecules in approximate order of decreasing S N 1 reactivity and decreasing S N 2 reactivity. () (b) CI (d) CI (f)

Give the major product(s) of each of the following reactions. (a) (b) (c) (d) (e) (f) H;C I HO H

The following reaction sequence gives rise to two isomeric products. What are they? Explain the mechanism of their formation. OH 1. Mg 2. D.O `CH3

Dienes may be prepared by elimination reactions of substituted allylic compounds. For example, Propose detailed mechanisms for each of these 2-methyl-1,3-butadiene (isoprene) syntheses. CH3 CH3 CH3...

Hexadeuteriobenzene, C 6 D 6 , is a very useful solvent for 1 H NMR spectroscopy because it dissolves a wide variety of organic compounds and, being aromatic, is very stable. Suggest a method for the...

(a) 3-Phenylpropanoyl chloride, C 6 H 5 CH 2 CH 2 COCl, reacts with AlCl 3 to give a single product with the formula C 9 H 8 O and an 1 H NMR spectrum with signals at = 2.53 (t, J = 8 Hz, 2 H), 3.02...

2,3-Diphenylcyclopropenone forms an addition product with HBr that exhibits the properties of an ionic salt. Suggest a structure for this product and a reason for its existence as a stable entity....

The 1 H NMR spectrum of the most stable isomer of [14]annulene shows two signals, at = -0.61 (4 H) and 7.88 (10 H) ppm. Two possible structures for [14]annulene are shown here. How do they differ?...

Explain the following reaction and the indicated stereochemical result mechanistically.

Reaction review. Without consulting the Reaction Road Map, suggest a combination of reagent and monosubstituted benzene that would give each of the following compounds. Refer to Table 16-2 for...

Reaction review. The preparation of the following compounds requires more than one step. As in Problem 41, suggest a monosubstituted benzene as starting material and the reagents for all the steps...

Underline the a-carbons and circle the a-hydrogens in each of the following structures. H;C. CH3 (a) CH;CH,CH,CH, (b) CH,CCH(CH,h (c) CH, H,C. CH3 CHO CH, (d) (e) (g) (CH3);CCH (h) (CH3),CCHCH

Write the structures of every enol and enolate ion that can arise from each of the carbonyl compounds illustrated in Problem 32. Data From Problem 32 H;C. CH3 (a) CH;CH,CH,CH3 (b) CH;CCH(CH3)2 () CH3...

Give the product(s) of the following reaction sequences. 1. , * 2. 1. , * 2. (CH),CH.CI 3. ', . CH,Br 3. H., . () CH,CO (b) CH2CHO

Would the use of an enamine instead of an enolate improve the likelihood of successful alkylation of a ketone by a secondary haloalkane?

When 3-methyl-1,3-diphenyl-2-butanone is treated with excess D2O in the presence of catalytic acid, some of its hydrogens are replaced by deuterium. How many? (a) One; (b) Two; (c) Three; (d) Six;...

The 1 H NMR spectrum of 2,4-pentanedione indicates the presence of an enol tautomer of the dione. What is its most likely structure? H;C, c=c=c_ OH OH OH () (b) () (d) CH3

Treatment of cyclopentane-1,3-dione with iodomethane in the presence of base leads mainly to a mixture of three products. (a) Give a mechanistic description of how these three products are formed....

Give the expected products of reaction of butanal with each of the following reagents. (a) LiAlH 4 , (CH 3 CH 2 ) 2 O, then H + , H 2 O (b) CH 3 CH 2 MgBr, (CH 3 CH 2 ) 2 O, then H + , H 2 O (c) HOCH...

Give the expected products of reaction of 2-pentanone with each of the reagents in Problem 34. Data From Problem 34 (a) LiAlH 4 , (CH 3 CH 2 ) 2 O, then H + , H 2 O (b) CH 3 CH 2 MgBr, (CH 3 CH 2 ) 2...

Rank the group of molecules shown here in decreasing order of boiling point and solubility in water. Explain your answers. CH3 CH,OH

Give the expected product(s) of each of the following reactions. (a) (b) (c) (d) (e) (f) + excess CH,OH HO-

Rank each of the following groups of organic compounds in order of decreasing acidity. (a) (b) (c) (d) (e) CH;CH,CO,H, CH;CCH,OH, CH;CH,CH,OH

How would you expect the acidity of acetamide to compare with that of acetic acid? With that of acetone? Which protons in acetamide are the most acidic? Where would you expect acetamide to be...

Reaction review II. Without consulting the Reaction Road Map on p. 915, suggest reagents to convert hexanoic acid into each of the following compounds: (a) 1-hexanol; (b) hexanoic anhydride; (c)...

Propose two possible mechanisms for the following reaction. (Consider the possible sites of protonation in the molecule and the mechanistic consequences of each.) Devise an isotope-labeling...

Propose two possible mechanisms for the following reaction. (Consider the possible sites of protonation in the molecule and the mechanistic consequences of each.) Devise an isotope-labeling...

Select the acid with the highest K a (i.e., lowest pKa). (a) H 3 CCO 2 H (b) (c) (d) (d) Cl 2 CHCO 2 H CO,H I

Suggest structures for the products of each reaction in the following synthetic sequence. 1. H, H* 2. (CH,),C=CHCH,Br 3. H*, H,O 1. O. CH;CI; 2. Zn, CH,COOH 3. KMNO,, NaHCO, H HOCH,CH,OH, H C16H2602...

4- and 5-hydroxy acids can undergo acid-catalyzed intramolecular esterification to produce the corresponding lactone in good yield. Consider the following two examples of lactonization. Divide the...

The acid whose structure is shown in the margin can best be prepared via one of these sequences. Which one? (a) (b) (c) (d) HO,C C(CH3)3

Give the products of the reactions of pentanamide with the reagents given in Problem 39(a, e, f). Repeat for N,N-dimethylpentanamide. Data From Problem39(a, e, f) (a) NaOH, H 2 O, heat; then H + , H...

What reagents would be necessary to carry out the following transformations? (a) Cyclohexanecarbonyl chloride pentanoylcyclohexane; (b) 2-butenedioic (maleic) anhydride (Z)-2-butene1,4-diol; (c)...

Give the product(s) of the reaction of butanedioic (succinic) anhydride with each of the reagents in Problem 36. Data From Problem 36 (a) (CH 3 ) 2 CHOH (b) NH 3 (c) (d) LiAlH 4 , (CH3CH 2 ) 2 O;...

Draw the structure of each of the following compounds: (a) -butyrolactone; (b) -valerolactone; (c) -valerolactone; (d) -propiolactam; (e) -methyl-d-valerolactam; (f) N-methyl-g-butyrolactam.

Formulate a mechanism for the acid-catalyzed hydrolysis of 3-methylpentanamide shown on p. 948. Data From page 948. Base Hydrolysis of an Amide II.. CH3CH2CH2CNHCH3 II.. > CH3CH2CH2CO:- + CH3NH2 II.....

Show how each of the following molecules might be synthesized by Mannich or Mannich-like reactions. (a) (b) (c) (d) (e) N(CH3)2 =0

Give the products of reaction of the following aldehydes with catalytic N-dodecylthiazolium bromide. (a) (CH 3 ) 2 CHCHO; (b) C 6 H 5 CHO; (c) cyclohexanecarbaldehyde; (d) C 6 H 5 CH 2 CHO.

Write chemical equations to illustrate all primary reaction steps that can occur between a base such as ethoxide ion and a carbonyl compound such as acetaldehyde. Explain why the carbonyl carbon is...

Propose a synthesis of ketone C, which was central in attempts to synthesize several antitumor agents. Start with aldehyde A, lactone B, and anything else you need. H,C H2C A B C

Two of the following four compounds are more acidic than CH 3 OH (i.e., two of these have K a greater than methanol). Which ones? (a) A and B; (b) B and C; (c) C and D; (d) D and A; (e) D and B....

Devise a synthesis of each of the following substituted benzene derivatives, starting from benzene. (a) (b) (c) (d) (e) (f) (g) Br

The following mixed Claisen condensation works best when one of the starting materials is present in large excess. Which of the two starting materials should be present in excess? Why? What side...

Give the products of the following reactions. (a) (b) What are the results of reaction of the substance formed in (b) with each aldehyde in Problem 41, followed by hydrolysis in the presence of HgCl...

Compound C is asymmetric, has molecular formula C 5 H 10 O, and contains two methyl groups and a 3 functional group. It has a broad infrared absorption band in the 32003550-cm -1 region and no...

The name sec-butyl alcohol defines a specific structure but the name sec-pentyl alcohol is ambiguous. Explain.

Shown below are Newman projection formulas for (R,R)-, (S,S )-, and (R,S )-2,3-dichlorobutane. (a) Which is which? (b) Which formula is a meso compound?

If a sample of a pure substance that has two or more chirality centers has an observed rotation of zero, it could be a racemate. Could it possibly be a pure stereoisomer? Could it possibly be a pure...

The reactions of aldehydes and ketones with LiAlH 4 and NaBH 4 (Section 12.3) are nucleophilic additions to the carbonyl group. What is the nucleophile in these reactions?

What would be the major product formed in the Baeyer-Villiger oxidation of 3-methyl-2-butanone?

The vapor pressure of ethylene glycol at several temperatures is given below: (a) Construct a semilog plot of the vapor-pressure data and determine a linear expression for ln p* as a function of...

When cyclohexanol is dehydrated to cyclohexene, a gummy green substance forms on the bottom of the flask. Suggest what this residue might be, and propose a mechanism for its formation (as far as the...

Propose mechanisms for the nucleophilic acyl substitutions to form ethyl benzoate and N-methylacetamide as shown on the previous page.

Methyl p-nitrobenzoate has been found to undergo saponification faster than methyl benzoate. (a) Consider the mechanism of saponification, and explain the reasons for this rate enhancement. (b) Would...

What are the molecular and empirical formulas for each of the following compounds? H H H N=N N-N H. H H H H

State whether each of the following statements is true or false. Justify your answer in each case. (a) Sulfuric acid is a monoprotic acid. (b) HCl is a weak acid. (c) Methanol is a base.

Domino toppling is an event in which a large number of dominoes are lined up close together and then allowed to topple, one after the other. The disturbance that propagates along the line of dominoes...

The standard heat of the reaction is H r = 904:7 kJ. (a) Briefly explain what that means. Your explanation may take the form When ______ (specify quantities of reactant species and their physical...

A 25-mL sample of 0.50 M NaOH is combined with a 75-mL sample of 0.50 M NaOH. What is the concentration of the resulting NaOH solution?

Tell whether the two structures in each pair represent enantiomers or two molecules of the same compound in different orientations. a. b. c. Br. CI Br Cl I F and H F H

Examine Solved Problem 7.3. Your task is to prepare A in the highest possible yield by dehydrobromination. Which base would you use? Solved Problem 7.3 Using Zaitsevs rule, predict which would be the...

An unknown compound shows a weak molecular ion at m/z87 in the mass spectrum, and the only large peak is at m/z30. The IR spectrum follows. The NMR spectrum shows only three singlets: one of area 9...

Show how you would accomplish the following multistep syntheses. You may use any additional reagents and solvents you need. a. PhCH 2 CH 2 OH PhCH 2 CH 2 COOH b. c. d. e. f. CH3 CH2

A student synthesized Compound 1 (below). To purify the compound, he extracted it into aqueous base and then acidified the solution to protonate the acid so that he could extract it back into ether....

Draw diagrams to show the bonding in each of the following compounds: a. Calcium fluoride (CaF 2 ) b. Oxygen (O 2 ) c. Magnesium chloride (MgCl 2 ) d. Tetrachloromethane (CCl 4 ).

At room temperature and pressure (rtp), which of the substances listed below is: a. A solid element? b. A liquid element? c. A gaseous mixture? d. A solid mixture? e. A liquid compound? f. A solid...

Ethyl chloride is sold as a liquid (see photo) under pressure for use as a local skin anesthetic. Ethyl chloride boils at 12 C at atmospheric pressure. When the liquid is sprayed onto the skin, it...

There are 15 competitors in a camel race. How many ways are there of guessing the first three finishers?

The drawing shows the activities of three radioactive samples. Rank the samples according to half-life, largest first. (a) 2, 3, 1 (b) 1, 2, 3 (c) 3, 2, 1 (d) 1, 3, 2 (e) 3, 1,2 2 3 Time Activity

a. Write equations that describe: i. The 1st ionisation energy of calcium ii. The 3rd ionisation energy of potassium iii. The 2nd ionisation energy of lithium iv. The 5th ionisation energy of sulfur....

a. Calculate the volume occupied by 272 g of methane at a pressure of 250 kPa and a temperature of 54 C. (R = 8.31 J K 1 mol 1 ; M r methane = 16.0) b. The pressure exerted by 0.25 mol of carbon...

a. What is meant by the term ideal gas? b. Under what conditions do real gases differ from ideal gases? Give reasons for your answer.

Explain the following: a. Why are most metals strong, but ionic solids are brittle? b. Why is an alloy of copper and tin stronger than either copper or tin alone?

Use the oxidation number method to balance these equations. a. H 2 SO 4 + HI S + I 2 + H 2 O b. HBr + H 2 SO 4 Br 2 + SO 2 + H 2 O c. V 3+ + I 2 + H 2 O VO 2+ + I + H +

Explain why the enthalpy change of neutralisation of one mole of sulfuric acid, H 2 SO 4 , is not the standard enthalpy change of neutralisation.

Use the information in Figure 6.15 and the information below to show that the average bond energy of the C H bond is 415.9 kJ mol 1 H f [CH 4 ] = 74.8 kJ mol 1 H at [ 12 H 2 ] = +218 kJ mol 1 H ...

a. What would happen if octane was added to a solution of sodium hydroxide? b. Explain your answer to part a.

Determine the base units of: a. Pressure (= force/area) b. Energy (= force distance) c. Density (= mass/volume)

Carbon-fibre-reinforced plastic (CRP) is used in the manufacture of golf clubs and tennis rackets. a. What are composite materials? b. Which two substances are used to manufacture this composite...

Determine the speed in m s 1 of an object that travels: a. 3.0 m in 5.0 ms b. 6.0 km in 3.0 Ms c. 8.0 pm in 4.0 ns.

A ray of light, in air, strikes one side of a rectangular glass block. The refractive index of the glass is 1.5. a. Draw a diagram to show the direction the ray will take in the glass if the angle of...

In the diagrams above, rays of light strike a mirror and one end of an optical fibre. a. Copy and complete the diagrams to show what will happen to each of the rays. b. Which diagram shows an example...

A car is moving at 8.0 m s 1 . The driver makes it accelerate at 1.0 m s 2 for a distance of 18 m. What is the final velocity of the car?

A car is initially stationary. It has a constant acceleration of 2.0 m s 2 . a. Calculate the velocity of the car after 10 s. b. Calculate the distance travelled by the car at the end of 10 s. c....

A train is travelling at 50 m s 1 when the driver applies the brakes and gives the train a constant deceleration of magnitude 0.50 m s 2 for 100 s. Describe what happens to the train. Calculate the...

An aircraft, starting from rest accelerates uniformly along a straight runway. It reaches a speed of 200 km h 1 and travels a distance of 1.4 km. What is the acceleration of the aircraft along the...

A submarine uses sonar to measure the depth of water below it. Reflected sound waves are detected 0.40 s after they are transmitted. How deep is the water? (Speed of sound in water = 1500 m s 1 .)

The volume of a rectangular block can be calculated using this equation: volume = length x width X height Using this information, copy and complete the table below. height/cm volume of rectangular...