Info Mla
an evacuated chamber, where it is bombarded with a beam of high-energy electrons. The electron beam knocks other electrons from the sample molecules, which become positively charged ions. Some of these ionized molecules survive, and others fragment into smaller ions. The various ions of different masses are then accelerated by an electric field and passed between the poles of a strong magnet, which deflects them through a curved, evacuated pipe. The radius of deflection of a charged ion M as it...
Ho Oh 1
24.58 Starch and cellulose are both polymers of glucose. What is the main structural difference between them, and what different roles do they serve in nature 24.59 Starch and glycogen are both a-linked polymers of glucose. What is the structural difference between them, and what different roles do they serve in nature 24.60 Write the open-chain structure of a ketotetrose. 24.61 Write the open-chain structure of a four-carbon deoxy sugar. 24.62 D-Mannose, an aldohexose found in orange peels,...
Constitutional Isomers
Isomers that have different connections among their constituent atoms are called constitutional isomers. Of the various types of constitutional isomers, we'll discuss just two linkage isomers and ionization isomers. Linkage isomers arise when a ligand can bond to a metal through either of two different donor atoms. For example, the nitrite NO2_ ion forms two different pentaamminecobalt III complexes a yellow nitro complex that contains a Co-N bond, Co NH3 5 NO2 2 , and a red nitrito complex...
A Foul-smelling Gas Produced By The Reaction Of With Was Collected And A 1.00
Ordinary lead pencils actually are made of a form of carbon called graphite. If a pencil line is 0.35 mm wide and the diameter of a carbon atom is 1.5 X 10-10 m, how many atoms wide is the line Begin with the known information, and set up an equation using appropriate conversion factors so that the unwanted units cancel. In the present instance, let's begin with the width of the pencil line in millimeters, then convert to meters, and then divide the line width in meters by the diameter of a...
Info Mjp
b Calculate the rate constant. c Calculate the rate of decomposition when the acetone concentration is 1.8 X 10-3 M. 12.47 The initial rates listed in the table were determined for the thermal decomposition of azomethane CH3NNCH3
Info Rnz
There's no point in trying to synthesize a substance from its elements under standard-state conditions if the substance has a positive value of aG f. Such a substance would have to be prepared at other temperatures and or pressures, or it would have to be made from alternative starting materials using a reaction that has a negative free-energy change. Thus, a knowledge of thermodynamics can save considerable time in chemical synthesis. In Section 17.8, we calculated standard free-energy changes...
AH Pro
. . . and this is larger for the solution, . . . . . . then this is smaller for the solution. What is the molality of an aqueous glucose solution if the boiling point of the solution at 1 atm pressure is 101.27 C The molal boiling-point-elevation constant for water is given in Table 11.4. Rearrange the equation for molal boiling-point elevation to solve for m where Kb 0.51 00 kg mol and ATb 101.270C - 100.000C 1.270C. SOLUTION
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2.35 In addition to carbon monoxide CO and carbon dioxide CO2 , there is a third compound of carbon and oxygen called carbon suboxide. If a 2.500 g sample of carbon suboxide contains 1.32 g of C and 1.18 g of O, show that the law of multiple proportions is followed. 2.36 The atomic mass of carbon 12.011 amu is approximately 12 times that of hydrogen 1.008 amu . a Show how you can use this knowledge to calculate possible formulas for benzene, ethane, and ethyl-ene Problem 2.34 . b Show how your...
General Problems 1
2.88 Germanium has five naturally occurring isotopes 70Ge, 20.5 , 69.924 amu 72Ge, 27.4 , 71.922 amu 73Ge, 7.8 , 72.923 amu 74Ge, 36.5 , 73.921 amu and 76Ge, 7.8 , 75.921 amu. What is the atomic mass of germanium 2.89 The best balances commonly found in laboratories can weigh amounts as small as 10 5 g. If you were to count out carbon atoms at the rate of two per second, how long would it take you to count a pile of atoms large enough to weigh 2.90 Name the following compounds a NaBrO3 b H3PO4...
A Solution Prepared By Dissolving 20.0 Mg Of Insulin In Water And Diluting To A
FIGURE 11.16 A schematic for the desalination of seawater by reverse osmosis. By applying a pressure on the seawater that is greater than osmotic pressure, water is forced through the osmotic membrane from the seawater side to the pure water side. FIGURE 11.16 A schematic for the desalination of seawater by reverse osmosis. By applying a pressure on the seawater that is greater than osmotic pressure, water is forced through the osmotic membrane from the seawater side to the pure water side....
Info Res
If 0.0050 mol of NO2 is introduced into a 1.0 L flask and allowed to decompose at 650 K, how many seconds does it take for the NO2 concentration to drop to 0.0010 M 12.121 Use the following initial rate data to determine the activation energy in kJ mol for the reaction A B C Initial Rate of Formation of C M s
The Ph Of 0.250m Hf Is 2.036. What Is The Value Of Ka For Hydrofluoric Acid
The pH of 0.250 M HF is 2.036. What is the value of Ka for hydrofluoric acid First, write the balanced equation for the dissociation equilibrium and the equilibrium equation that defines Ka. To obtain a value for Ka, we need to calculate the concentrations of the various species in the equilibrium mixture. We begin by calculating the H3 O concentration from the pH. Because dissociation of one HF molecule gives one H3 O ion and one F_ ion, the H3 O and F_ concentrations are equal. The HF...
Free Energy and Chemical Equilibrium
Now that we've seen how aG for a reaction depends on composition, we can understand how the total free energy of a reaction mixture changes as the reaction progresses toward equilibrium. Look again at the expression for calculating aG If the reaction mixture contains mainly reactants and almost no products, Q will be much less than 1 and RT ln Q will be a very large negative number minus infinity when Q 0 . Consequently, no matter what the value of aG positive or negative , the negative RT ln Q...
Info Lce
14.55 In the oxyacetylene torch, how many grams of acetylene and how many liters of O2 at STP are needed to generate 1000 kJ of heat 14.56 Write a balanced equation for the reaction of an excess of O2 with each of the following elements a Li b P c Al d Si 14.57 Write a balanced equation for the reaction of an excess of O2 with each of the following elements a Ca b C c As d B 14.58 Draw some electron-dot structures for O2, and explain why they are inconsistent with the paramagnetism of O2 and...
Additional Problems Vpx
Electron Configurations and Properties of Transition Elements 20.26 Use the periodic table to give the electron configuration for each of the following atoms and ions 20.27 Specify the electron configuration for each of the following atoms and ions 20.28 Predict the number of unpaired electrons for each of the following 20.29 Predict the number of unpaired electrons for each of the following 20.30 Titanium, used to make jet aircraft engines, is much harder than potassium or calcium. Explain....
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species 35Cl 2, 35Cl37Cl, and 3 Cl 2 What would the atmospheric pressure be in millimeters of mercury if our atmosphere were composed of pure CO2 gas The surface temperature of Venus is about 1050 K, and the pressure is about 75 Earth atmospheres. Assuming that these conditions represent a Venusian STP, what is the standard molar volume in liters of a gas on Venus When you look directly up at the sky, you are actually looking through a very tall, transparent column of air that extends from the...
O Ipv
Bassam Z. Shakhashiri, Buffering Action and Capacity, Chemical Demonstrations, A Handbook for Teachers of Chemistry, Vol. 3 The University of Wisconsin Press, Madison, 1989 pp. 173-185. We sometimes talk about the buffering ability of a solution using the term buffer capacity as a measure of the amount of acid or base that the solution can absorb without a significant change in pH. Buffer capacity is also a measure of how little the pH changes with the addition of a given amount of acid or...
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a Which of the solutions are buffer solutions b Which solution has the greatest buffer capacity 16.35 The following pictures represent solutions that contain a weak acid HA pKa 6.0 and its sodium salt NaA. Na ions and solvent water molecules have been omitted for clarity.
O Oed
a Which compound has the highest melting point b Which compound has the lowest boiling point c Which compounds yield H2 gas when they are mixed together 14.27 The following pictures represent the structures of oxides of carbon and sulfur. Which has the stronger bonds Explain. 14.28 Explain what is meant by an isotope effect, and give two examples. 14.29 How can protium and deuterium be separated 14.30 Calculate the percentage mass difference between a H and 2H b 2H and 3H Would you expect the...
Info Pzv
10.62 Use the plot you made in Problem 10.60 to find a value in kJ mol for AHvap for dichloromethane. 10.63 Use the plot you made in Problem 10.61 to find a value in kJ mol for AHvap for mercury. The normal boiling point of mercury is 630 K. 10.64 Choose any two temperatures and corresponding vapor pressures in the table given in Problem 10.60, and use those values to calculate AHvap for dichloromethane in kJ mol . How does the value you calculated compare to the value you read from your plot...
Solution Xpo
H3 O antilog - pH 10- pH 10-45 3 X 10-5 M H3 O is reported to only one significant figure because the pH has only one digit beyond the decimal point. If you need help in finding the antilog of a number, see Appendix A.2. Ballpark Check Because a pH of 4.5 is between 4 and 5, H3 O is between 10-4 M and 10-5 M, in agreement with the solution. PROBLEM 15.8 Calculate the pH of each of the following solutions a A sample of seawater that has an OH - concentration of 1.58 X 10-6 M b A sample of acid...
Liquid Butane The Fuel Used In Many Disposable Lighters Has And A Density Of
As the world's petroleum deposits become ever more scarce, other sources of energy will have to be found to replace them. Hydrogen, although it burns cleanly and is relatively nonpolluting, has two drawbacks low availability and low combustion enthalpy per milliliter. Ethanol and methanol look like good current choices for alternative fuels because both can be produced relatively cheaply and have reasonable combustion enthalpies. Ethanol can be produced from wood by the breakdown of cellulose...
When 1.000 Mol Of Pcl5 Is Introduced Into A 5.000l Container At 500k 78.50
The equilibrium constant Kc for this reaction is 1.51 X 102 in benzene solution, but only 3.7 X 10-2 in water solution. a Calculate the ratio of dimers to monomers for 0.100 M acetic acid in benzene. b Calculate the ratio of dimers to monomers for 0.100 M acetic acid in water. c Why is Kc for the water solution so much smaller than Kc for the benzene solution 13.105 Consider the reaction C s CO2 g L 2 CO g . When 1.50 mol of CO2 and an excess of solid carbon are heated in a 20.0 L container at...
Info Ufh
The proton that is transferred to water when the acid dissociates is shown in color. The proton that is transferred to water when the acid dissociates is shown in color. PROBLEM 15.12 The pH of 0.10 M HOCl is 4.23. Calculate Ka for hypochlorous acid, and check your answer against the value given in Table 15.2. KEY CONCEPT PROBLEM 15.13 The following pictures represent aqueous solutions of three acids HA A X, Y, or Z water molecules have been omitted for clarity KEY CONCEPT PROBLEM 15.13 The...
Stereoisomers
Isomers that have the same connections among atoms but a different arrangement of the atoms in space are called stereoisomers. In coordination chemistry, there are two kinds of stereoisomers diastereoisomers and enantiomers we'll discuss the latter in Section 20.9 . Y j Hannia Lujan-Upton, Introducing Stereochemistry to Non-Science Majors, J. Chem. Educ, Vol. 78, 2001, 475-477. FIGURE 20.18 Diastereoisomers of the square planar complex Pt NH3 2 Cl2. The two compounds have the same connections...
Info Ofn
a Write the equilibrium constant expressions for Kp and Kc. b The value of Kp at 500 C is 12. What is the value of c A sample of butane having a pressure of 50 atm is heated at 500 C in a closed container at constant volume. When equilibrium is reached, what percentage of the butane has been converted to ethane and eth-ylene What is the total pressure at equilibrium d How would the percent conversion in part c be affected by a decrease in volume 13.109 The equilibrium constant Kc for the...
Info Odr
23.69 Draw structures corresponding to the following IUPAC names 23.70 Ignoring cis-trans isomers, there are five alkenes with the formula C5Hj0. Draw structures for as many as you can, and give their IUPAC names. Which can exist as cis-trans isomers 23.71 There are three alkynes with the formula C5H8. Draw and name them. 23.72 Which of the following compounds are capable of cis-trans isomerism 23.73 Which of the following compounds are capable of cis-trans isomerism
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a Sketch the final equilibrium state of the system. b What are the signs , -, or 0 of AH, AS, and AG for this process Explain. c How does this process illustrate the second law of thermodynamics d Is the reverse process spontaneous or nonsponta-neous Explain. 17.21 What are the signs , -, or 0 of AH, AS, and AG for the spontaneous sublimation of a crystalline solid 17.22 What are the signs , -, or 0 of AH, AS, and AG for the spontaneous condensation of a vapor to a liquid Explain.
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20.118 In octahedral complexes, the choice between high-spin and low-spin electron configurations arises only for d4-d7 complexes. Explain. 20.119 Draw a crystal field energy-level diagram, and predict the number of unpaired electrons for each of the following 20.120 Explain why CoCl4 2- blue and Co H2O 6 2 pink have different colors. Which complex has its absorption bands at longer wavelengths 20.121 The complex Rh en 2 NO2 SCN can exist in 12 isomeric forms, including constitutional isomers...
I Lbl
When hydrates are heated, the water is driven off. If you heat blue crystals of CuSO4 5 H2O above 350 C, for example, you'll observe formation of anhydrous copper sulfate, CuSO4, a white compound Figure 14.13 . Some anhydrous compounds are so prone to forming hydrates that they absorb water from the atmosphere. Anhydrous Mg ClO4 2, for example, picks up water from air, yielding Mg ClO4 2 6 H2O. Compounds that absorb water from the air are said to be hygroscopic and are often useful as drying...
According To The Equation For The Balmer Line Spectrum Of Hydrogen A Value Of N
Problems 5.1-5.22 appear within the chapter. 5.23 Where on the blank outline of the periodic table do elements that meet the following descriptions appear a Elements with the valence-shell ground-state electron configuration ns2 np5 b An element whose fourth shell contains two p electrons c An element with the ground-state electron configuration Ar 4s2 3d10 4p5 5.24 Where on the periodic table do elements that meet the following descriptions appear a Elements with electrons whose largest...
O Xpd
9.33 A glass tube has one end in a dish of mercury and the other end closed by a stopcock. The distance from the surface of the mercury to the bottom of the stopcock is 800 mm. The apparatus is at 25 C, and the mercury level in the tube is the same as that in the dish. 9.32 Effusion of a 1 1 mixture of two gases through a small pinhole produces the results shown below. a Which gas molecules yellow or blue have a higher average speed b If the yellow molecules have a molecular mass of 25 amu,...
General Problems Pdn
18.100 Consider a galvanic cell that uses the following half-reactions MnO4 aq 8 H aq 5 e - gt a Write a balanced equation for the overall cell reaction. b What is the oxidizing agent, and what is the reducing agent c Calculate the standard cell potential. 18.101 Given the following half-reactions and E values, Mn3 aq e - gt Mn2 aq E 1.54 V MnO2 s 4 H aq e - gt Mn3 aq 2 H2O 1 write a balanced equation for disproportionation of Mn3 aq , and calculate the value of E for this reaction. Is the...
Info Bpr
The Henry's-law constant of methyl bromide CH3 Br , a gas used as a soil fumigating agent, is k 0.159 mol L atm at 25 C. What is the solubility in mol L of methyl bromide in water at 25 C and a partial pressure of 125 mm Hg According to Henry's law, the solubility of a gas in water equals k P. The solubility of methyl bromide in water at a partial pressure of 125 mm Hg is 0.0261 M. PROBLEM 11.11 The solubility of CO2in water is 3.2 X 10_2 Mat 25 C and 1 atm pressure. What is the Henry's-law...
MultiConcept Problems Xfc
17.117 A mixture of NO2 and N2 O4, each at an initial partial pressure of 1.00 atm and a temperature of 100 C, is allowed to react. Use the data in Appendix B to calculate the partial pressure of each gas at equilibrium. You may assume that AH and AS are independent of temperature. 17.118 A mixture of 14.0 g of N2 and 3.024 g of H2 in a 5.00 L container is heated to 400 C. Use the data in Appendix B to calculate the molar concentrations of N2, H2, and NH3 at equilibrium. Assume that AH and AS...
Info Twq
a Write a balanced equation for the reaction. b What is the reaction order with respect to A, B, and C, and what is the overall reaction order d Is a catalyst involved in this reaction Explain. e Suggest a mechanism that is consistent with the data. f Calculate the rate constant for the formation of D. 12.106 What fraction of the molecules in a gas at 300 K collide with an energy equal to or greater than Ea when Ea equals 50 kJ mol What is the value of this fraction when Ea is 100 kJ mol...
Info Qoo
FIGURE 20.19 Diastereoisomers of the Co NH3 4 Cl2 ion. Although they may appear different, cis isomers a and b are identical, as can be seen by rotating the entire complex by 90 about a Cl - Co - NH3 axis. Similarly, trans isomers c and d are identical. In general, square planar complexes of the type MA2 B2 and MA2 BC where M is a metal ion and A, B, and C are ligands can exist as cis-trans isomers. No cis-trans isomers are possible, however, for four-coordinate tetrahedral complexes because...
Additional Problems Sog
General Properties and Periodic Trends 19.20 Which element in each of the following pairs has the higher ionization energy a S or Cl b Si or Ge c In or O 19.21 Arrange the following elements in order of increasing ionization energy a P b K c Al d F 19.22 Which element in each of the following pairs has the larger atomic radius a B or Al b P or S c Pb or Br 19.23 Arrange the following elements in order of increasing atomic radius a As b O c Sn d S 19.24 Which element in each of the following...
Info Bju
11.34 Two beakers, one with pure water blue and the other with a solution of NaCl in water green , are placed in a closed container as represented by drawing a . Which of the drawings b - d represents what the beakers will look like after a substantial amount of time has passed 11.35 A phase diagram of temperature versus composition for a mixture of the two volatile liquids octane Q bp 69 C and decane bp 126 C is shown. Assume that you begin with a mixture containing 0.60 mol of decane and 0.40...
How Much Heat In Kilojoules Is Evolved Or Absorbed In Reaction Of 4.88 Of
The molar mass of Al is 26.98 g mol, so 5.00 g of Al equals 0.185 mol 5.00 g Al X 1 m l 0.185 mol Al 26.98 g Al Because 2 mol of Al releases 852 kJ of heat, 0.185 mol of Al releases 78.8 kJ of heat Ballpark Check Since the molar mass of Al is about 27 g, 5 g of aluminum is roughly 0.2 mol, and the heat evolved is about 852 2 kJ mol X 0.2 mol, or approximately 85 kJ. FIGURE 8.8 A calorimeter for measuring the heat flow in a reaction at constant pressure AH . The reaction takes place inside an...
If The Reverse Osmosis Equipment Can Exert A Maximum Pressure Of 100.0 At
When salt is spread on snow-covered roads at 2 C, the snow melts. When salt is spread on snow-covered roads at 30 C, nothing happens. Explain. How many grams of KBr dissolved in 125 g of water is needed to raise the boiling point of water to 103.2 C How many grams of ethylene glycol automobile antifreeze, C2 H6O2 dissolved in 3.55 kg of water is needed to lower the freezing point of water in an automobile radiator to 22.0 C When 1 mL of toluene is added to 100 mL of benzene bp 80.1 C , the...
Salts That Yield Acidic Solutions
Salts such as NH4Cl that are derived from a weak base NH3 and a strong acid HCl produce acidic solutions. In such a case, the anion is neither an acid nor a base, but the cation is a weak acid NH4 aq H2O l H3 O aq NH3 aq Related ammonium salts derived from amines, such as CH3NH3 Cl, CH3 2NH2 Cl, and CH3 3NH Cl, also give acidic solutions because they too have cations with at least one dissociable proton. The pH of a solution that contains an acidic cation can be calculated by the standard...
Info Qrr
Notice in Figure 5.14b that as n becomes larger and approaches infinity, the energy difference between the n shell and the first shell converges to a value of 1312 kJ mol. That is, 1312 kJ is released when electrons come from a great distance the infinite shell and add to H to give a mole of hydrogen atoms, each with an electron in its first shell H e - gt H Energy 1312 kJ mol Because the energy released on adding an electron to H is equal to the energy absorbed on removing an electron from a...
Info Sxc
2.74 Which of the following compounds are acids and which are bases a HI b CsOH c H3 PO4 2.75 For each of the acids you identified in Problem 2.74, tell how many H ions can be donated from one molecule of acid. 2.76 Identify the anion that results when each of the acids in Problem 2.74 dissolves in water. 2.77 Identify the cation that results when each of the bases in Problem 2.74 dissolves in water. 2.78 Write formulas for the following binary compounds 2.79 Write formulas for the following...
Additional Problems Usy
9.34 What is temperature a measure of 9.35 Why are gases so much more compressible than solids or liquids 9.36 Atmospheric pressure at the top of Pikes Peak in Colorado is approximately 480 mm Hg. Convert this value to atmospheres and to pascals. 9.37 Carry out the following conversions 9.38 What is the pressure in millimeters of mercury inside a container of gas connected to a mercury-filled open-end manometer of the sort shown in Figure 9.4 when the level in the arm connected to the container...
General Problems Ige
8.96 When 1.50 g of magnesium metal is allowed to react with 200 mL of 6.00 M aqueous HCl, the temperature rises from 25.0 C to 42.9 C. Calculate AH in kilojoules for the reaction, assuming that the heat capacity of the calorimeter is 776 J C, that the specific heat of the final solution is the same as that of water 4.18 J g C , and that the density of the solution is 1.00 g mL. 8.97 Use the data in Appendix B to find standard enthalpies of reaction in kilojoules for the following processes b 2...
Boron Compounds
Boron Halides The boron halides are highly reactive, volatile, covalent compounds that consist of trigonal planar BX3 molecules. At room temperature, BF3 and BCl3 are gases, BBr3 is a liquid, and BI3 is a low-melting solid mp 43 C . In their most important reactions, the boron halides behave as Lewis acids. For example, BF3 reacts with ammonia to give the Lewis acid-base adduct F3 B -NH3 Section 15.16 it reacts with metal fluorides, yielding salts that contain the tetra-hedral BF4- anion and it...
Aqueous Reactions and Net Ionic Equations
The equations we've been writing up to this point have all been molecular equations. That is, all the substances involved in reactions have been written using their full formulas as if they were molecules. In Section 4.1, for example, we wrote the precipitation reaction of lead II nitrate with potassium iodide to yield solid Pbl2 using only the parenthetical aq to indicate that the reaction takes place in aqueous solution. Nowhere was it indicated that ions are involved In fact, lead nitrate,...
Predicting the Direction of Reaction
Consider again the gaseous reaction of hydrogen with iodine H2 g I2 g 2 HI g Kc 57.0 at 700 K Suppose that we have a mixture of H2 g , I2 g , and HI g at 700 K with concentrations H2 t 0.10 M, I2 t 0.20 M, and HI t 0.40 M. The subscript t on the concentration symbols means that the concentrations were measured at some arbitrary time t, not necessarily at equilibrium. If we substitute these concentrations into the equilibrium constant expression, we obtain a value called the reaction quotient...
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8.78 What does entropy measure 8.79 What are the two terms that make up the free-energy change for a reaction, AG, and which of the two is usually more important 8.80 How is it possible for a reaction to be spontaneous yet endothermic 8.81 Is it possible for a reaction to be nonspontaneous yet exothermic Explain. 8.82 Tell whether the entropy changes for the following processes are likely to be positive or negative a The fizzing of a newly opened can of soda b The growth of a plant from seed...