Show how each of the following compounds could be prepared from 3-pentanone. In most cases more than one synthetic transformation will be necessary. (a) 2-Bromo-3-pentanone (b) 1-Penten-3-one (c)...
Identify the reagents appropriate for each step in the following syntheses: (a) (b) (c) (d) CH CH CH 0 HCCH-CH-CH-CH-CH - CHi (CHCH CCH3 CH-CCH-CH-CHCH-CH-_ CH(CH3)2 H(CH3)2...
(a) For a long time attempts to prepare compound A were thwarted by its ready isomerization to compound B. The isomerization is efficiently catalyzed by traces of base. Write a reasonable mechanism...
Give an acceptable IUPAC name for each of the following: (a) CH3(CH2)6CO2H (b) CH3(CH2)6CO2K (c) CH2==CH(CH2)5CO2H (d) (e) HO2C(CH2)6CO2H (f) CH3(CH2)4CH(CO2H)2 H C (CH24CO2H -
Show by a series of equations how you could synthesize each of the following compounds from the indicated starting material and any necessary organic or inorganic reagents: (a) 2-Methylpropanoic acid...
(a) Which stereoisomer of 4-hydroxycyclohexanecarboxylic acid (cis or trans) can form a lactone? Make a molecular model of this lactone. What is the conformation of the cyclohexane ring in the...
A certain carboxylic acid (C14H26O2), which can be isolated from whale blubber or sardine oil, yields non anal and O==CH(CH2)3CO2H on ozonolysis. What is the structure of this acid?
Write a structural formula for each of the following compounds: (a) 2-Phenylbutanoic anhydride (b) Butyl 2-phenylbutanoate (c) 2-Phenylbutyl butanoate (d) 2-Phenylbutanamide (e) N-Ethyl-2-...
On the basis of the general mechanism for basic hydrolysis shown in Figure 20.7, write an analogous sequence for the hydrolysis of N,N-dimethylformamide, HN(CH3)2
Write a structural formula for each of the following compounds: (a) M-Chlorobenzoyl bromide (b) Trifluoroacetic anhydride (c) Cis-1,2-Cyclopropanedicarboxylic anhydride (d) Ethyl...
Write an equation showing the preparation of the following amides from the indicated carboxylic acid derivative: (a) (b) 0 CH3CNHCH3 from an acid anhydride HCN(CH3) from a methyl ester
Write a structural formula for the principal organic product or products of each of the following reactions: (a) Acetyl chloride and bromobenzene, AlCl3 (b) Acetyl chloride and 1-butanethiol (c)...
Apply the knowledge gained by studying Table 20.2 to help you predict the major organic product obtained by reaction of benzoyl chloride with each of the following: (a) Benzoic acid (b) Ethanol (c)...
Ambrettolide is obtained from hibiscus and has a musk-like odor. Its preparation from a compound A is outlined in the table that follows. Write structural formulas, ignoring stereochemistry, for...
Write the structure of the tetrahedral intermediate formed in each of the reactions given in Problem 20.3. Using curved arrows, show how each tetrahedral intermediate dissociates to the appropriate...
Apply the knowledge gained by studying Table 20.3 to help you predict the major organic product of each of the following reactions: (a) Acetic anhydride + ammonia (2 mol) (b) Phthalic anhydride +...
A certain compound has a molecular weight of 83 and contains nitrogen. Its infrared spectrum contains a moderately strong peak at 2270 cm-1. Its 1H and 13C NMR spectra are shown in Figure 20.10. What...
Aryl halides react too slowly to undergo substitution by the SN2 mechanism with the sodium salt of diethyl malonate, and so the phenyl substituent of phenobarbital cannot be introduced in the way...
All the following questions concern ethyl (2-oxocyclohexane)carboxylate. (a) Write a chemical equation showing how you could prepare ethyl (2 oxocyclohexane)car-boxylate by a Dieckmann reaction. (b)...
(a) Only a small amount (less than 0.01%) of the enol form of diethyl malonate is present at equilibrium. Write a structural formula for this enol. (b) Enol forms are present to the extent of about...
(a) On addition of one equivalent of methylmagnesium iodide to ethyl acetoacetate, the Grignard reagent is consumed, but the only organic product obtained after working up the reaction mixture is...
Assign alkanamine names to N-methylethylamine and to N,Ndimethylcycloheptylamine.
Arrange the following compounds or anions in each group in order of decreasing basicity: (a) H3C, H2N, HO, F (b) H2O, NH3, HO, H2N (c) (d) HO , H,N,:C=N:, NO,
Arrange the members of each group in order of decreasing basicity: (a) Ammonia, aniline, methylamine (b) Acetanilide, aniline, N-methylaniline (c) 2,4-Dichloroaniline, 2,4-dimethylaniline,...
Apply the Henderson-Hasselbalch equation (see "Quantitative Relationships Involving Carboxylic Acids," the box accompanying Section 19.4) to calculate the CH3NH3+/CH3NH2 ratio in water buffered at pH...
Alkylation of ammonia is sometimes employed in industrial processes; the resulting mixture of amines is separated by distillation. The ultimate starting materials for the industrial preparation of...
An article in the October 1998 issue of the Journal of Chemical Education (p. 1266) describes the following reaction. Fluoxetine hydrochloride (Prozac) is a widely prescribed antidepressant drug...
A method for the generation of benzyne involves heating the diazonium salt from o-aminobenzoic acid (benzenediazonium-2-carboxylate). Using curved arrows, show how this substance forms benzyne. What...
A synthesis of the analgesic substance phenacetin is outlined in the following equation. What is the structure of phenacetin? L CH,CH Br. NaOH p-Nitrophenol 2 Fe, HCE then HO > phenacetin 3. CH COCCH
A number of compounds of the type represented by compound A were prepared for evaluation as potential analgesic drugs. Their preparation is described in a retrosynthetic format as shown. On the basis...
Predict the products formed when each of the following isotopically substituted derivatives of chlorobenzene is treated with sodium amide in liquid ammonia. Estimate as quantitatively as possible the...
As an allergen for testing purposes, synthetic 3-pentadecylcatechol is more useful than natural poison ivy extracts (of which it is one component). A stable crystalline solid, it is efficiently...
How many ketotetroses are possible? Write Fischer projections for each.
A synthesis of triacylglycerols has been described that begins with the substance shown. Outline a series of reactions suitable for the preparation of a triacylglycerol of the type illustrated in the...
Arachidonic acid is the biosynthetic precursor to PGE2. The structures of PGE1 (see Figure 26.5) and PGE2 are identical except that PGE2 has one more double bond than PGE1. Suggest a reasonable...
Amino acid analysis of a certain tetrapeptide gave alanine, glycine, phenylalanine, and valine in equimolar amounts. What amino acid sequences are possible for this tetrapeptide?
Starting with phenylalanine and glycine, outline the steps in the preparation of Phe-Gly by the Merrifield method.
Acrylonitrile (CH2=CHC=N) readily undergoes conjugate addition when treated with nucleophilic reagents. Describe a synthesis of -alanine that takes advantage of this fact. (H3NCH2CH2CO2)
(a) The 5-nucleotide of inosine, inosinic acid (C10H13N4O8P), is added to foods as a flavor enhancer. What is the structure of inosinic acid? (The structure of inosine is given in Problem 27.38.) (b)...
A graduated cylinder is fi lled to the 40.00-mL mark with a mineral oil. The masses of the cylinder before and after the addition of the mineral oil are 124.966 g and 159.446 g, respectively. In a...
You are given a liquid. Briefly describe steps you would take to show whether it is a pure substance or a homogeneous mixture.
Do the following statements describe chemical or physical properties? (a) Oxygen gas supports combustion. (b) Fertilizers help to increase agricultural production. (c) Water boils below 100C on top...
Classify each of the following as an element, a compound, a homogeneous mixture, or a heterogeneous mixture: (a) Seawater, (b) Helium gas, (c) Sodium chloride (table salt), (d) A bottle of soft...
(a) Normally the human body can endure a temperature of 105F for only short periods of time without permanent damage to the brain and other vital organs. What is this temperature in degrees Celsius?...
Three apprentice tailors (X, Y, and Z) are assigned the task of measuring the seam of a pair of trousers. Each one makes three measurements. The results in inches are X (31.5, 31.6, 31.4); Y (32.8,...
A slow jogger runs a mile in 13 min. Calculate the speed in (a) in/s, (b) m/min, (c) km/h. (1 mi 5 1609 m; 1 in = 2.54 cm.)
A resting adult requires about 240 mL of pure oxygen/min and breathes about 12 times every minute. If inhaled air contains 20 percent oxygen by volume and exhaled air 16 percent, what is the volume...
(a) Referring to Problem 1.69, calculate the total volume (in liters) of air an adult breathes in a day. (b) In a city with heavy traffic, the air contains 2.1 x 10-6 L of carbon monoxide (a...
A student is given a crucible and asked to prove whether it is made of pure platinum. She first weighs the crucible in air and then weighs it suspended in water (density = 0.9986 g/mL). The readings...
A sheet of aluminum (Al) foil has a total area of 1.000 ft2 and a mass of 3.636 g. What is the thickness of the foil in millimeters? (Density of Al = 2.699 g/cm3.) 1.89 Comment on whether each of the...
A monatomic ion has a charge of + 2. The nucleus of the parent atom has a mass number of 55. If the number of neutrons in the nucleus is 1.2 times that of the number of protons, what is the name and...
Describe the changes in properties (from metals to nonmetals or from nonmetals to metals) as we move (a) Down a periodic group (b) Across the periodic table from left to right.
What are the empirical formulas of the following compounds? (a) Al2Br6, (b) Na2S2O4, (c) N2O5, (d) K2Cr2O7
(a) Describe Rutherford's experiment and how it led to the structure of the atom. How was he able to estimate the number of protons in a nucleus from the scattering of the a particles? (b) Consider...
Fluorine reacts with hydrogen (H) and deuterium (D) to form hydrogen fluoride (HF) and deuterium fluoride (DF), where deuterium (21H) is an isotope of hydrogen. Would a given amount of fluorine react...
A research chemist used a mass spectrometer to study the two isotopes of an element. Over time, she recorded a number of mass spectra of these isotopes. On analysis, she noticed that the ratio of the...
An iron bar weighed 664 g. After the bar had been standing in moist air for a month, exactly one-eighth of the iron turned to rust (Fe2O3). Calculate the final mass of the iron bar and rust.
A certain metal oxide has the formula MO where M denotes the metal. A 39.46-g sample of the compound is strongly heated in an atmosphere of hydrogen to remove oxygen as water molecules. At the end,...
An impure sample of zinc (Zn) is treated with an excess of sulfuric acid (H2SO4) to form zinc sulfate (ZnSO4) and molecular hydrogen (H2). (a) Write a balanced equation for the reaction. (b) If...
Carbohydrates are compounds containing carbon, hydrogen, and oxygen in which the hydrogen to oxygen ratio is 2:1. A certain carbohydrate contains 40.0 percent carbon by mass. Calculate the empirical...
Analysis of a metal chloride XCl3 shows that it contains 67.2 percent Cl by mass. Calculate the molar mass of X and identify the element.
A mixture of NaBr and Na2 SO4 contains 29.96 percent Na by mass. Calculate the percent by mass of each compound in the mixture.
A mixture of CuSO4? 5H2O and MgSO4? 7H2O is heated until all the water is lost. If 5.020 g of the mixture gives 2.988 g of the anhydrous salts, what is the percent by mass of CuSO4? 5H2O in the...
A mixture of methane (CH4) and ethane (C2H6) of mass 13.43 g is completely burned in oxygen. If the total mass of CO2 and H2O produced is 64.84 g, calculate the fraction of CH4 in the mixture.
Suppose you are given a cube made of magnesium (Mg) metal of edge length 1.0 cm. (a) Calculate the number of Mg atoms in the cube. (b) Atoms are spherical in shape. Therefore, the Mg atoms in the...
Air is a mixture of many gases. However, in calculating its "molar mass" we need consider only the three major components: nitrogen, oxygen, and argon. Given that one mole of air at sea level is made...
A die has an edge length of 1.5 cm. (a) What is the volume of one mole of such dice? (b) Assuming that the mole of dice could be packed in such a way that they were in contact with one another,...
A reaction having a 90 percent yield may be considered a successful experiment. However, in the synthesis of complex molecules such as chlorophyll and many anticancer drugs, a chemist often has to...
A sample of iron weighing 15.0 g was heated with potassium chlorate (KClO3) in an evacuated container. The oxygen generated from the decomposition of KClO3 converted some of the Fe to Fe2O3. If the...
A sample containing NaCl, Na2 SO4, and NaNO3 gives the following elemental analysis: Na: 32.08 percent; O: 36.01 percent; Cl: 19.51 percent. Calculate the mass percent of each compound in the sample.
A sample of 10.00 g of sodium reacts with oxygen to form 13.83 g of sodium oxide (Na2O) and sodium peroxide (Na2O2). Calculate the percent composition of the mixture.
How many atoms are present in 3.14 g of copper (Cu)?
All of the substances listed below are fertilizers that contribute nitrogen to the soil. Which of these is the richest source of nitrogen on a mass percentage basis? (a) Urea, (NH2)2 CO (b) Ammonium...
Allicin is the compound responsible for the characteristic smell of garlic. An analysis of the compound gives the following percent composition by mass: C: 44.4 percent; H: 6.21 percent; S: 39.5...
Ammonia is a principal nitrogen fertilizer. It is prepared by the reaction between hydrogen and nitrogen. In a particular reaction, 6.0 moles of NH3 were produced. How many moles of H2 and how many...
The depletion of ozone (O3) in the stratosphere has been a matter of great concern among scientists in recent years. It is believed that ozone can react with nitric oxide (NO) that is discharged from...
A sample of a compound of Cl and O reacts with an excess of H2 to give 0.233 g of HCl and 0.403 g of H2 O. Determine the empirical formula of the compound.
Acetic acid (CH 3 COOH) is an important ingredient of vinegar. A sample of 50.0 mL of commercial vinegar is titrated against a 1.00 M NaOH solution. What is the concentration (in M ) of acetic acid...
A quantitative definition of solubility is the maximum number of grams of a solute that will dissolve in a given volume of water at a particular temperature. Describe an experiment that would enable...
An ionic compound X is only slightly soluble in water. What test would you employ to show that the compound does indeed dissolve in water to a certain extent?
A student is given an unknown that is either iron(II) sulfate or iron(III) sulfate. Suggest a chemical procedure for determining its identity.
A student found that a sulfuric acid solution caused the light bulb to glow brightly. However, after the addition of a certain amount of a barium hydroxide [Ba(OH)2] solution, the light began to dim...
A useful application of oxalic acid is the removal of rust (Fe2O3) from, say, bathtub rings according to the reaction Fe,O3(s) + 6H;C,04(ag) 2Fe(C,O4) (aq) + 3H,0 + 6H* (aq)
Acetylsalicylic acid (C9H8O4) is a monoprotic acid commonly known as "aspirin." A typical aspirin tablet, however, contains only a small amount of the acid. In an experiment to determine its...
Ammonium nitrate (NH4NO3) is one of the most important nitrogen-containing fertilizers. Its purity can be analyzed by titrating a solution of NH4NO3 with a standard NaOH solution. In one experiment a...
A quantity of 25.0mL of a solution containing both Fe2+ and Fe3+ ions is titrated with 23.0mL of 0.0200 M KMnO4 (in dilute sulfuric acid). As a result, all of the Fe2+ ions are oxidized to Fe3+ ions....
A 22.02-mL solution containing 1.615g Mg(NO3)2 is mixed with a 28.64-mL solution containing 1.073g NaOH. Calculate the concentrations of the ions remaining in solution after the reaction is complete....
Two aqueous solutions of AgNO 3 and NaCl are mixed. Which of the following diagrams best represents the mixture?
For the complete redox reactions given here, write the half-reactions and identify the oxidizing and reducing agents: (a) (b) (c) (d) Cl2 + 2NaBr_ 2NaCl + Br- Si + 2F,-> SF
Arrange the following species in order of increasing oxidation number of the sulfur atom: (a) H2S, (b) S8 (c) H2SO4, (d) S2-, (e) HS-, (f) SO2, (g) SO3.
Calculate the volume in mL of a solution required to provide the following: (a) 2.14 g of sodium chloride from a 0.270 M solution, (b) 4.30 g of ethanol from a 1.50 M solution, (c) 0.85 g of acetic...
A sample of 0.6760 g of an unknown compound containing barium ions is dissolved in water and treated with an excess of Na2SO4. If the mass of the BaSO4 precipitate formed is 0.4105 g, what is the...
A quantity of 18.68 mL of a KOH solution is needed to neutralize 0.4218 g of KHP. What is the concentration (in molarity) of the KOH solution?
What volume of a 0.500 M HCl solution is needed to neutralize each of the following: (a) 10.0 mL of a 0.300 M NaOH solution (b) 10.0 mL of a 0.200 M Ba(OH)2 solution
A sample of iron ore (containing only Fe2+ ions) weighing 0.2792 g was dissolved in dilute acid solution, and all the Fe(II) was converted to Fe(III) ions. The solution required 23.30mL of 0.0194 M...
A healthy adult exhales about 5.0 102 mL of a gaseous mixture with each breath. Calculate the number of molecules present in this volume at 37C and 1.1 atm. List the major components of this gaseous...
A mixture of Na2CO3 and MgCO3 of mass 7.63 g is reacted with an excess of hydrochloric acid. The CO2 gas generated occupies a volume of 1.67 L at 1.24 atm and 26C. From these data, calculate the...
About 8.0 106 tons of urea [(NH2)2 CO] are used annually as a fertilizer. The urea is prepared at 200C and under high-pressure conditions from carbon dioxide and ammonia (the products are urea and...
Acidic oxides such as carbon dioxide react with basic oxides like calcium oxide (CaO) and barium oxide (BaO) to form salts (metal carbonates). (a) Write equations representing these two reactions....
A top Mt. Everest, the atmospheric pressure is 210 mmHg and the air density is 0.426 kg/m3. (a) Calculate the air temperature, given that the molar mass of air is 29.0 g/mol. (b) Assuming no change...