A 0.0500-mol sample of a nutrient substance is burned in a bomb calorimeter containing 2.00 × 102 g H2O. If the formula weight of this nutrient substance is 114 g/mol, what is the fuel value (in nutritional Cal) if the temperature of the water increased 5.700C?
> Solve the combined gas law expression for the final temperature.
> Name each of the following compounds: a. N2O4 b. CCl4 c. N2O5
> The balloon described in Question 5.49 was then placed in a refrigerator at 398F. Calculate its new volume. Question 5.49: A balloon containing a sample of helium gas is warmed in an oven. If the balloon measures 1.25 L at room temperature (200C), what
> Determine the change in volume that takes place when a 2.00-L sample of N2(g) is heated from 250 K to 500 K.
> Describe how you would distinguish experimentally between a colloidal dispersion and a suspension.
> Write the correct formula for each of the following: a. manganese (II) oxide b. manganese (III) oxide
> The temperature on a summer day may be 908F. Convert this value to Kelvin units.
> State Charles’s law in equation form.
> A balloon filled with helium gas at 1.00 atm occupies 15.6 L. What volume would the balloon occupy in the upper atmosphere at a pressure of 0.150 atm?
> At what temperature will 2.00 mol of He fill a 2.00-L container at standard pressure?
> Calculate the Boyle’s law constant at a pressure of 2 atm.
> What is the volume of the gas at a pressure of 5 atm?
> By what factor will the volume of the gas in Question 5.33 change? Question 5.33: The pressure on a fixed mass of a gas is tripled at constant temperature. Will the volume increase, decrease, or remain the same?
> State Boyle’s law in equation form.
> Name each of the following ions: a. Cu2+ b. Fe2+ c. Fe3+
> Explain the relationship you described in the answer to Question 17.24 for the effect of the number of carbon-carbon double bonds in fatty acids on their melting points. Question 17.24: As the number of carbon-carbon double bonds in fatty acids increas
> Do gases exhibit more ideal behavior at low or high temperatures? Why?
> Why do gases with lower molar masses diffuse more rapidly than gases with higher molar masses?
> Why are gas densities much lower than those of liquids or solids?
> Name each of the following compounds: a. Li2CO3 b. FeBr2 c. CuSO4
> Express each of the following in units of atm: a. 128 cm Hg b. 255 torr c. 1405 mm Hg d. 303 kPa
> Describe the molecular/atomic basis of gas pressure.
> What is the trend for atom size from top to bottom down a group?
> Why is diamond used as an industrial cutting tool?
> Describe one property that is characteristic of: a. molecular solids b. metallic solids
> Distinguish between amorphous and crystalline solids.
> Which of the following pairs of atoms and ions are isoelectronic? a. Cl-, Ar b. Na+, Ne c. Mg2+, Na+ d. Li+, Ne e. O2-, F- f. N3-, Cl-
> Predict the compound expected to have the greatest surface tension in the liquid state ннн H ннн H H H Н—С—С—С—н н—С —С—С—Н н—с—с—С—Н H нн H он он propane isopropyl alcohol propylene glycol
> Which of these molecules would you expect to have the highest boiling point? Why? H H. Н—С — Н H-C-CI H-C-0--H H H methane chloromethane methanol
> Which of these molecules exhibit dipole-dipole forces? Why? H H. Н—С — Н H-C-CI H-C-0--H H H methane chloromethane methanol
> Distinguish between the terms evaporation and boiling.
> How can the periodic table be used to determine the number of valence electrons in a representative element atom?
> Convert 3.0 m to: a. yd b. in c. ft d. cm e. mm
> Identify the element for each of the orbital diagrams (once corrected) in Question 2.91. Question 2.91: а. 1s 2s 2p b. 1s 2s 2p C. 1s 2s 2p
> Ozone, O3, has two resonance forms. Draw each form.
> Using the periodic table, write the electron configuration of each of the following atoms: a. Ca b. Fe c. Cl
> Ethylamine is an example of an important class of organic compounds. The molecular formula of ethylamine is CH3CH2NH2. Draw its Lewis structure.
> What is the role of coenzyme A in the reaction catalyzed by pyruvate dehydrogenase?
> Formaldehyde, H2CO, in water solution has been used as a preservative for biological specimens. Draw the Lewis structure of formaldehyde.
> How is a 2s orbital different from a 1s orbital?
> Refer to the periodic table, and find the following information: a. the symbol of the noble gas in period 3 b. the element in Group IVA (or 14) with the smallest mass c. the only metalloid in Group IIIA (or 13) d. the element whose atoms contain 18 proto
> True or false? Molecules that have only polar bonds will always be polar. Explain your reasoning.
> What is the bond angle of a tetrahedral molecule?
> For each of the elements Ca, K, Cu, Zn, Br, and Kr, provide the following information: a. Which are metals? b. Which are representative metals? c. Which are inert or noble gases?
> Which group of the periodic table is known as the noble gases? List their names.
> Rank the following in order of increasing bond length: single bond, double bond, triple bond
> Use LeChatelier’s principle to predict the effects, if any, of each of the following changes on the equilibrium system, described below, in a closed container. C(s) + 2H2 (g) ↽−−−−⇀ CH4 (g) + 18 kcal a. C is added. b. H2 is added. c. CH4 is removed. d.
> Calculate the pH of a solution that is: a. 1.0 × 10-1 M in HCl b. 1.0 × 10-5 M in HNO3
> Express each of the following in units of psi: a. 12.5 cm Hg b. 46.0 torr c. 254 mm Hg d. 0.48 atm
> A 0.325-mol sample of ammonium nitrate was dissolved in water producing a 4.00 × 102 g solution. The temperature decreased from 25.08C to 15.70C. If the specific heat of the resulting solution is 1.00 cal/g · 0C, calculate the quantity of energy absorbed
> What is plane-polarized light?
> a. Why is DNA polymerase said to be template-directed? b. Why is DNA replication a self-correcting process?
> Why don’t proteins turn around in biological membranes like revolving doors?
> What enzymatic reactions of gluconeogenesis bypass the irreversible steps of glycolysis?
> Why are there several alternative mRNA sequences that could encode the same peptide?
> Explain the feedforward activation mechanism that results in the activation of pyruvate kinase.
> Explain the role of allosteric enzymes in control of glycolysis.
> Contrast ionic and covalent compounds with respect to their relative melting points.
> Except for the functional groups attached to the rings, the nitrogenous bases are largely flat, hydrophobic molecules. Explain why the arrangement of the purines and pyrimidines found in DNA molecules is very stable.
> A balloon, filled with an ideal gas, has a volume of 5.00 L at 500F. At what temperature (0F) would the balloon’s volume double?
> Which of the following structures have incorrect IUPAC names? If incorrect, give the correct IUPAC name. a. CH,C=CCH,CH(CH), 2-Methyl-4-hexyne b. CH,CH2, CH,CH, CH,CH, н H. 3-Ethyl-3-hexene c. CH,CH(CH,)CH,C=CCH,CH(CH,) CH,CH, с. 2-Edhy-7-methyl-4-о
> What is the function of the enzyme primase?
> Describe the stages of protein digestion, including the location of each.
> Saturated fatty acids have higher melting points than monounsaturated fatty acids. Polyunsaturated fatty acids have even lower melting points. Develop a hypothesis to explain this observation.
> Discuss the digestion of dietary carbohydrates, lipids, and proteins.
> a. What is the ultimate goal of genetic engineering? b. What ethical issues does this goal raise?
> How do the sulfa drugs selectively kill bacteria while causing no harm to humans?
> How is it possible for sickle cell trait to confer a survival benefit on the person who possesses it?
> List the functions of each of the coenzymes. What classes of enzymes would require these coenzymes?
> a. What properties are associated with molecular solids? b. Provide two examples of molecular solids.
> How many protons, neutrons, and electrons are present in a single atom of: a. phosphorus-30 b. sulfur-32 c. chlorine-35
> Why was the Benedict’s reagent useful for determining the amount of glucose in the urine?
> Describe the classification of the R groups of the amino acids, and provide an example of each class.
> Can you think of any disadvantage associated with the use of isotopes described in Question 9.13? Explain. Question 9.13: Describe the advantage of using isotopes with short half-lives for tracer applications in a medical laboratory.
> How does extremely low pH cause proteins to coagulate?
> Explain the difference between the d- and l-designation and the (1) and (2) designation.
> Why would you predict that a carboxylic acid would be more polar and have a higher boiling point than an alcohol of comparable molar mass?
> Write an equation representing the reaction catalyzed by each of the enzymes listed in Practice Problem 19.1e through i at the end of Example 19.1. (Hint: You may need to refer to the index of this book to learn more about the substrates and the reaction
> How is LDL taken into cells?
> How can structural analogs serve as enzyme inhibitors?
> What is the benefit for an enzyme such as triacylglycerol lipase to be regulated by covalent modification, in this case phosphorylation?
> Calculate the [HCO3-]/[H2CO3] that corresponds to a pH of 7.4. The Ka for carbonic acid is 4.2 × 10-7.
> What is the difference between lactose intolerance and galactosemia?
> Explain why genetic mutations that result in the replacement of one amino acid with another can lead to the formation of a protein that cannot carry out its biological function.
> Describe the series of experiments that characterized the electron.
> What are the principal uses of methanol, ethanol, and isopropyl alcohol?
> Write the structure of each of the following peptides: a. Lys-trp-pro b. Gln-ser-his c. Arg-met-asp
> Write an equation to show a reaction that would produce each of the following amines: a. 1-Pentanamine b. N, N-Dimethylethanamine c. N-Ethyl propanamine
> A typical concentration of magnesium ion in certain types of intravenous solutions is 3 meq/L. Represent this concentration in mol/L.
> What is the function of lactic acid in food products? Of what significance is lactic acid in muscle metabolism?
> Is the solution osmolarity that you calculated in Question 6.11 isotonic with blood plasma? Why or why not? Question 6.11: Refer to the intravenous solution in Figure 6.7 and calculate the osmolarity of its contents. Figure 6.7: Composition and conce
> a. Draw and name all of the isomeric products obtained from the monobromination of propane with Br2/ light. If halogenation were a completely random reaction and had an equal probability of occurring at any of the C—H bonds in a molecule, what percentage
> Predict which compound in each of the following pairs should have the higher melting and boiling points (Hint: Write the Lewis structure and determine whether the compound is ionic, polar covalent, or nonpolar covalent.): a. C2H6 and CH4 c. F2 and Br2 b
> Why do the hydrocarbon tails of membrane phospholipids provide a barrier between the inside and outside of the cell?
> How does the structure of amylose differ from that of amylopectin and glycogen?
> State Hund’s rule. Determine whether the following orbital diagrams violate Hund’s rule. а. 1s 2s 2p b. 1s 2s 2p C. 1s 2s 2p
> List the functions of several a-globulins.
> By comparing two solutions: 0.50 M sodium chloride (an ionic compound) and 0.50 M sucrose (a covalent compound). Each solution is separated from water by a semipermeable membrane. Which solution has the higher osmotic pressure?
> Distinguish among the three types of glycosphingolipids, cerebrosides, sulfatides, and gangliosides.
> Describe the purpose of a titration.
