Chemistry Physical Chemistry8b08

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1 Million+ Step-by-step solutionsmath books Q:A car owner who knows no chemistry has to putA car owner who knows no chemistry has to put antifreeze in his car’s radiator. The instructions recommend a mixture of 30% ethylene glycol and 70% water. Thinking he will improve his protection he uses pure ethylene glycol. He is saddened to find that the solution does not provide as much protection as he hoped. Why not?
Q:Calculate the freezing point of a 0.100 m aqueous solutionCalculate the freezing point of a 0.100 m aqueous solution of K2SO4,
(a) Ignoring interionic attractions, and
(b) Taking interionic into consideration by using the van’t Hoff factor (Table 13.4)?
Q:Carbon disulfide (CS2) boils at 46.30 oC and has aCarbon disulfide (CS2) boils at 46.30 oC and has a density of 1.261 g/mL.
Q:A lithium salt used in lubricating grease has the formulaA lithium salt used in lubricating grease has the formula LiCnH2n+1O2. The salt is soluble in water to the extent of 0.036 g per 100 g of water at 25 oC. The osmotic pressure of this solution is found to be 57.1 torr. Assuming that molality and molarity in such a dilute solution are the same and that the lithium salt is completely dissociated in the solution, determine an appropriate value of n in the formula for the salt.

Q:Fluorocarbons (compounds that contain both carbon and fluorine) were, untilFluorocarbons (compounds that contain both carbon and fluorine) were, until recently, used as refrigerants. The compounds listed in the following table are all gases at 25 oC, and their solubilities in water at and 1 atm fluorocarbon pressure are given as mass percentages.
Q:At ordinary body temperature (37 oC) the solubility of N2At ordinary body temperature (37 oC) the solubility of N2 in water in contact with air at ordinary atmospheric pressure (1.0 atm) is 0.015 g/L. Air is approximately 78 mol % N2. Calculate the number of moles of N2 dissolved per liter of blood, which is essentially an aqueous solution. At a depth of 100 ft in water, the pressure is 4.0 atm. What is the solubility of N2 from air in blood at this pressure? If a scuba diver suddenly surfaces from this depth, how many milliliters of N2 gas, in the form of tiny bubbles, are released into the bloodstream from each liter of blood?
Q:Consider of following values for enthalpy of vaporization (kJ/mol) ofConsider of following values for enthalpy of vaporization (kJ/mol) of several organic substances:
Consider of following values for enthalpy of vaporization (kJ/mol) ofConsider of following values for enthalpy of vaporization (kJ/mol) ofConsider of following values for enthalpy of vaporization (kJ/mol) ofConsider of following values for enthalpy of vaporization (kJ/mol) of

(a) Use variations in the intermolecular forces operating in these organic substances to account for their variations in heats of vaporization.
(b) How would you expect the solubilities of these substances to vary in hexane as solvent? In ethanol? Use intermolecular forces, including hydrogenbonding interactions where applicable, to explain your responses.

Q:A textbook on chemical thermodynamics states, “The heat of solutionA textbook on chemical thermodynamics states, “The heat of solution represents the difference between the lattice energy of the crystalline solid and the solvation energy of the gaseous ions.”
(a) Draw a simple energy diagram to illustrate this statement.
(b) A salt such as NaBr is insoluble in most polar non-aqueous solvents such as acetonitrile (CH3CN) or nitromethane (CH3NO2), but salts of large cations, such as tetramethylammonium bromide [(CH3)4NBr], are generally more soluble. Use the thermochemical cycle you drew in part (a) and the factors that determine the lattice energy (Section 8.2) to explain this fact?
Q:Suppose you had a balloon made of some highly flexibleSuppose you had a balloon made of some highly flexible semipermeable membrane. The balloon is filled completely with a 0.2 M solution of some solute and is submerged in a 0.1 M solution of the same solute:

Q:(a) A sample of hydrogen gas is generated in a(a) A sample of hydrogen gas is generated in a closed container by reacting 2.050 g of zinc metal with 15.0 mL of 1.00 M sulfuric acid. Write the balanced equation for the reaction, and calculate the number of moles of hydrogen formed, assuming that the reaction is complete.
Q:The following table presents the solubilities of several gases inThe following table presents the solubilities of several gases in water at 25 oC under a total pressure of gas and water vapor of 1 atm.
Q:A small cube of lithium (density = 0.535 g/cm3) measuringA small cube of lithium (density = 0.535 g/cm3) measuring 1.0 mm on edge is added to 0.500 L of water. The following reaction occurs:
2 Li(s) + 2 H2O(l) → LiOH(aq) + H2(g)
Q:At 35 oC the vapor pressure of acetone, (CH3)2CO, isAt 35 oC the vapor pressure of acetone, (CH3)2CO, is 360 torr, and that of chloroform, CHCl3, is 300 torr. Acetone and chloroform can form very weak hydrogen bonds between one another as follows:
At 35 oC the vapor pressure of acetone, (CH3)2CO, isQ:The molecule n-octylglucoside, shown here, is widely used in biochemicalThe molecule n-octylglucoside, shown here, is widely used in biochemical research as a nonionic detergent for “solubilizing” large hydrophobic protein molecules. What characteristics of this molecule are important for its use in this way?
The molecule n-octylglucoside, shown here, is widely used in biochemicalQ:In general, the attractive intermolecular forces between solvent and soluteIn general, the attractive intermolecular forces between solvent and solute particles must be comparable or greater than solute-solute interactions for significant solubility to occur. Explain this statement in terms of the overall energetics of solution formation?
Q:(a) Considering the energetics of solute-solute, solvent- solvent, and solute-solvent(a) Considering the energetics of solute-solute, solvent- solvent, and solute-solvent interactions, explain why NaCl dissolves in water but not in benzene (C6H6).
(b)What factors cause a cation to be strongly hydrated?
Q:Indicate the type of solute-solvent interaction (Section 11.2) that shouldIndicate the type of solute-solvent interaction (Section 11.2) that should be most important in each of the following solutions:
(a) CCl4 in benzene (C6H6),
(b) Methanol (CH3OH) in water,
(c) KBr in water,
(d) HCl in acetonitrile (CH3CN)?
Q:Indicate the principal type of solute-solvent interaction in each ofIndicate the principal type of solute-solvent interaction in each of the following solutions and rank the solutions from weakest to strongest solute-solvent interaction:
(a) KCl in water,
(b) CH2Cl2 in benzene (C6H6),
(c) Methanol (CH3OH) in water?
Q:An ionic compound has a very negative in water. WouldAn ionic compound has a very negative in water. Would you expect it to be very soluble or nearly insoluble in water? Explain in terms of the enthalpy and entropy changes that accompany the process?
Q:When ammonium chloride dissolves in water, the solution becomes colder. (a)When ammonium chloride dissolves in water, the solution becomes colder.
(a) Is the solution process exothermic or endothermic?
(b) Why does the solution form?
Q:(a) In Equation 13.1 which of the enthalpy terms for(a) In Equation 13.1 which of the enthalpy terms for dissolving an ionic solid would correspond to the lattice energy?
(b) Which energy term in this equation is always exothermic?
Q:The schematic diagram of the solution process as the netThe schematic diagram of the solution process as the net sum of three steps in Figure 13.4 does not show the relative magnitudes of the three components because these will vary from case to case. For the dissolution of LiCl in water, (soIn = – 37 KJ/Mol. Which of the three enthalpy changes would you expect to be much more negative than the other two? Explain
Q:When two nonpolar organic liquids such as hexane (C6H14) andWhen two nonpolar organic liquids such as hexane (C6H14) and heptane (C7H16) are mixed, the enthalpy change that occurs is generally quite small.
(a) Use the enthalpy diagram in Figure 13.4 to explain why.
Q:The enthalpy of solution of KBr in water is aboutThe enthalpy of solution of KBr in water is about + 198 kJ/Mol. Nevertheless, the solubility of KBr in water is relatively high. Why does the solution process occur even though it is endothermic?
Q:The solubility of Cr(NO3)3 ( 9 H2O in water isThe solubility of Cr(NO3)3 ( 9 H2O in water is 208 g per 100 g of water at 15oC. A solution of Cr(NO3)3 ( 9 H2O in water at is formed by dissolving 324 g in 100 g water. When this solution is slowly cooled to 15oC, no precipitate forms.
(a) What term describes this solution?
(b) What action might you take to initiate crystallization? Use molecular-level processes to explain how your suggested procedure works?
Q:The solubility of MnSO4 ( H2O in water at 20oCThe solubility of MnSO4 ( H2O in water at 20oC is 70 g per 100 mL of water.
Q:By referring to Figure 13.18, determine whether the addition ofBy referring to Figure 13.18, determine whether the addition of 40.0 g of each of the following ionic solids to 100 g of water at 40oC will lead to a saturated solution:
(a) NaNO3,
(b) KCl,
(c) K2Cr2O7,
(d) Pb(NO3)2.
Q:By referring to Figure 13.18, determine the mass of eachBy referring to Figure 13.18, determine the mass of each of the following salts required to form a saturated solution in 250 g of water at 30 oC:
(a) KClO3,
(b) Pb(NO3)2,
(c) Ce2(SO4)3.
Q:Water and glycerol, CH2(OH)CH(OH)CH2OH, are miscible in all proportions. WhatWater and glycerol, CH2(OH)CH(OH)CH2OH, are miscible in all proportions. What does this mean? How do the OH groups of the alcohol molecule contribute to this miscibility?
Q:Oil and water are immiscible. What does this mean? ExplainOil and water are immiscible. What does this mean? Explain in terms of the structural features of their respective molecules and the forces between them?
Q:Common laboratory solvents include acetone (CH3COCH3), methanol (CH3OH), toluene (C6H5CH3),Common laboratory solvents include acetone (CH3COCH3), methanol (CH3OH), toluene (C6H5CH3), and water. Which of these is the best solvent for nonpolar solutes? Explain.
Q:How does the lattice energy of an ionic solid affectHow does the lattice energy of an ionic solid affect its solubility in water?
Q:Would you expect alanine (an amino acid) to be moreWould you expect alanine (an amino acid) to be more soluble in water or in hexane? Explain.
Would you expect alanine (an amino acid) to be moreQ:(a) Would you expect stearic acid, CH3(CH2)16COOH, to be more(a) Would you expect stearic acid, CH3(CH2)16COOH, to be more soluble in water or in carbon tetrachloride? Explain.
(b) Which would you expect to be more soluble in water, cyclohexane or dioxane? Explain.
(a) Would you expect stearic acid, CH3(CH2)16COOH, to be more(a) Would you expect stearic acid, CH3(CH2)16COOH, to be moreQ:Ibuprofen, widely used as a pain reliever, has a limitedIbuprofen, widely used as a pain reliever, has a limited solubility in water, less than 1 mg/mL. Which feature of the molecule contributes to its low solubility in water, and which feature contributes to its solubility?
Ibuprofen, widely used as a pain reliever, has a limited

Ibuprophen

Q:Which of the following in each pair is likely toWhich of the following in each pair is likely to be more soluble in hexane, C6H14:
(a) CCl4 or CaCl2;
(b) Benzene (C6H6) or glycerol, CH2(OH)CH(OH)CH2OH;
(c) Octanoic acid, CH3CH2CH2CH2CH2CH2CH2COOH, or acetic acid, CH3COOH? Explain your answer in each case.
Q:Which of the following in each pair is likely toWhich of the following in each pair is likely to be more soluble in water:
(a) Cyclohexane (C6H12) or glucose (C6H12O6) (Figure 13.12);
(b) Propionic acid (CH3CH2COOH) or sodium propionate (CH3CH2COONa);
(c) HCl or ethyl chloride (CH3CH2Cl)? Explain in each case.
Q:(a) Explain why carbonated beverages must be stored in sealed(a) Explain why carbonated beverages must be stored in sealed containers.
(b) Once the beverage has been opened, why does it maintain more carbonation when refrigerated than at room temperature?
Q:Explain why pressure substantially affects the solubility of O2 inExplain why pressure substantially affects the solubility of O2 in water but has little effect on the solubility of NaCl in water?
Q:The Henry’s law constant for helium gas in water inThe Henry’s law constant for helium gas in water in 30 oC is 3.7 × 10-4 M/atm and the constant for N2 at 30 oC is 6.0 × 10-4 M/atm. If the two gases are each present at 1.5 atm pressure, calculate the solubility of each gas?
Q:The partial pressure of O2 in air at sea levelThe partial pressure of O2 in air at sea level is 0.21 atm. Using the data in Table 13.1, together with Henry’s law, calculate the molar concentration of O2 in the surface water of a mountain lake saturated with air at 20 oC and an atmospheric pressure of 650 torr?
Q:(a) Calculate the mass percentage of Na2SO4 in a solution(a) Calculate the mass percentage of Na2SO4 in a solution containing 10.6 g Na2SO4 in 483 g water.
(b) An ore contains 2.86 g of silver per ton of ore. What is the concentration of silver in ppm?
Q:A quantity of the blue solid on the left inA quantity of the blue solid on the left in Figure 13.7 is placed in an oven and heated for a time. It slowly turns from blue to the white of the solid on the right. What has occurred?
Q:(a) What is the mass percentage of iodine (I2) in(a) What is the mass percentage of iodine (I2) in a solution containing 0.035 mol I2 in 125 g of CCl4?
(b) Seawater contains per 0.0079 g Sr2+ kilogram of water. What is the concentration of Sr2+ measured in ppm?
Q:A solution is made containing 14.6 g of CH3OH inA solution is made containing 14.6 g of CH3OH in 184 g H2O. Calculate
(a) The mole fraction of CH3OH,
(b) The mass percent of CH3OH,
(c) The molality of CH3OH.
Q:A solution is made containing 20.8 g phenol (C6H5OH) inA solution is made containing 20.8 g phenol (C6H5OH) in 425 g ethanol (C2H5OH). Calculate
(a) The mole fraction of phenol,
(b) The mass percent of phenol,
(c) The molality of phenol?
Q:Calculate the molarity of the following aqueous solutions: (a) 0.540 gCalculate the molarity of the following aqueous solutions:
(a) 0.540 g Mg(NO3)2 in 250.0 mL of solution,
(b) 22.4 g LiCIO4 ( 3 H2O in 125 mL of solution,
(c) 25.0 mL of 3.50 M HNO3 diluted to 0.250 L.
Q:What is the molarity of each of the following solutions: (a)What is the molarity of each of the following solutions:
(a) 15.0 g Al2(SO4)3 in 0.250 mL solution,
(b) 5.25 g in 175 mL of solution,
(c) 35.0 mL of 9.00 M H2SO4 diluted to 0.500 L?
Q:Calculate the molality of each of the following solutions: (a) 8.66Calculate the molality of each of the following solutions:
(a) 8.66 g benzene (C6H6) dissolved in 23.6 g carbon tetrachloride (CCl4),
(b) 4.80 g NaCl dissolved in 0.350 L of water?
Q:(a) What is the molality of a solution formed by(a) What is the molality of a solution formed by dissolving 1.12 mol of KCl in 16.0 mol of water?
(b) How many grams of sulfur (S8) must be dissolved in 100.0 g naphthalene (C10H8) to make a 0.12 m solution?
Q:A sulfuric acid solution containing 571.6 g of H2SO4 perA sulfuric acid solution containing 571.6 g of H2SO4 per liter of solution has a density of 1.329 g/cm3. Calculate
(a) The mass percentage,
(b) The mole fraction,
(c) The molality,
(d) The molarity of H2SO4 in this solution?
Q:Ascorbic acid (vitamin C, C6H8O6) is a water-soluble vitamin.Ascorbic acid (vitamin C, C6H8O6) is a water-soluble vitamin.
Q:The density of acetonitrile (CH3CN) is 0.786 g/mL and theThe density of acetonitrile (CH3CN) is 0.786 g/mL and the density of methanol (CH3OH) is 0.791 g/mL. A solution is made by dissolving 22.5 mL CH3OH in 98.7 mL CH3CN.
(a) What is the mole fraction of methanol in the solution?
(b)What is the molality of the solution?
(c) Assuming that the volumes are additive, what is the molarity of CH3OH in the solution?
Q:Which of the following is the best representation of aWhich of the following is the best representation of a saturated solution? Explain your reasoning.

Q:The density of toluene (C7H8) is 0.876, and the densityThe density of toluene (C7H8) is 0.876, and the density of thiophene (C4H4S) is 1.065 g/mL. A solution is made by dissolving 8.10 g of thiophene in 250.0 mL of toluene.
(a) Calculate the mole fraction of thiophene in the solution.
(b) Calculate the molality of thiophene in the solution.
(c) Assuming that the volumes of the solute and solvent are additive, what is the molarity of thiophene in the solution?
Q:Calculate the number of moles of solute present in eachCalculate the number of moles of solute present in each of the following aqueous solutions:
(a) 600 mL of 0.250 M SrBr2,
(b) 86.4 g of 0.180 m KCl,
(c) 124.0 g of a solution that is 6.45% glucose (C6H12O6) by mass.
Q:Calculate the number of moles of solute present in eachCalculate the number of moles of solute present in each of the following solutions:
(a) 255 mL of 1.50 M HNO3(aq),
(b) 50.0 mg of an aqueous solution that is 1.50 m NaCl,
(c) 75.0 g of an aqueous solution that is 1.50% sucrose (C12H22O11) by mass?
Q:Describe how you would prepare each of the following aqueousDescribe how you would prepare each of the following aqueous solutions, starting with solid KBr:
(a) 0.75 L of 1.5 × 10-2 M KBr,
(b) 125 g of 0.180 m KBr,
(c) 1.85 L of a solution that is by mass (the density of the solution is 1.10g/mL),
(d) A 0.150 M solution of KBr that contains just enough KBr to precipitate 16.0 g of AgBr from a solution containing 0.480 mol of AgNO3?
Q:Describe how you would prepare each of the following aqueousDescribe how you would prepare each of the following aqueous solutions:
(a) 1.50 L of 0.110 M (NH4)2SO4 solution, starting with solid (NH4)2SO4;
(b) 225 g of a solution that is 0.65 m in Na2CO3, starting with the solid solute;
(c) 1.20 L of a solution that is Pb(NO3)2 by mass (the density of the solution is 1.16 g/mL), starting with solid solute;
(d) a 0.50 M solution of HCl that would just neutralize 5.5 g of Ba(OH)2 starting with 6.0 M HCl?
Q:Commercial aqueous nitric acid has a density of 1.42 g/mLCommercial aqueous nitric acid has a density of 1.42 g/mL and is 16 M. Calculate the percent HNO3 by mass in the solution?
Q:Commercial concentrated aqueous ammonia is 28% NH3 by mass andCommercial concentrated aqueous ammonia is 28% NH3 by mass and has a density of 0.90 g/mL. What is the molarity of this solution?
Q:Brass is a substitutional alloy consisting of a solution ofBrass is a substitutional alloy consisting of a solution of copper and zinc. A particular sample of red brass consisting of 80.0% Cu and 20.0% Zn by mass has a density of 8750 kg/m3.
(a) What is the molality of Zn in the solid solution?
(b) What is the molarity of Zn in the solution?
Q:Caffeine (C8H10N4O2) is a stimulant found in coffee and tea.Caffeine (C8H10N4O2) is a stimulant found in coffee and tea. If a solution of caffeine in chloroform (CHCl3) as a solvent has a concentration of 0.0500 m, calculate
(a) The percent caffeine by mass,
(b) The mole fraction of caffeine.

Caffeine
Q:During a typical breathing cycle, the CO2 concentration in theDuring a typical breathing cycle, the CO2 concentration in the expired air rises to a peak of 4.6% by volume. Calculate the partial pressure of the CO2 at this point, assuming 1 atm pressure. What is the molarity of the CO2 in air at this point, assuming a body temperature of 37 oC?
Q:The solubility of Xe in water at 1 atm pressureThe solubility of Xe in water at 1 atm pressure and 20 oC is approximately 5 × 10-3. Compare this with the solubilities of Ar and Kr in water (Table 13.1) and explain what properties of the rare gas atoms account for the variation in solubility?
Q:Breathing air that contains 4.0% by volume CO2 over timeBreathing air that contains 4.0% by volume CO2 over time causes rapid breathing, throbbing headache, and nausea, among other symptoms. What is the concentration of CO2 in such air in terms of
(a) Mol percentage,
(b) Molarity, assuming 1 atm pressure and a body temperature of 37 °C?
Q:How does increasing the concentration of a nonvolatile solute inHow does increasing the concentration of a nonvolatile solute in water affect the following properties:
(a) Vapor pressure,
(b) Freezing point,
(c) Boiling point;
(d) Osmotic pressure?
Q:Consider two solutions, one formed by adding 10 g ofConsider two solutions, one formed by adding 10 g of glucose (C6H12O6) to 1 L of water and the other formed by adding 10 g of sucrose (C12H22O11) to 1 L of water. Are the vapor pressures over the two solutions the same? Why or why not?
Q:(a) What is an ideal solution? (b) The vapor pressure of(a) What is an ideal solution?
(b) The vapor pressure of pure water at is 60 oC is 149 torr. The vapor pressure of water over a solution at 60 oC containing equal numbers of moles of water and ethylene glycol (a nonvolatile solute) is 67 torr. Is the solution ideal according to Raoult’s law? Explain.
Q:(a) Calculate the vapor pressure of water above a solution(a) Calculate the vapor pressure of water above a solution prepared by adding 22.5 g of lactose (C12H22O11) to 200.0 g of water at 338 K. (Vapor-pressure data for water are given in Appendix B.)
(b) Calculate the mass of propylene glycol (C3H8O2) that must be added to 0.340 kg of water to reduce the vapor pressure by 2.88 torr at 40 oC?
Q:(a) Calculate the vapor pressure of water above a solution(a) Calculate the vapor pressure of water above a solution prepared by dissolving 28.5 g of glycerin (C3H8O3) in 125 g of water at 343 K. (The vapor pressure of water is given in
Appendix B.)
(b) Calculate the mass of ethylene glycol (C2H6O2) that must be added to 1.00 kg of ethanol (C2H5OH) to reduce its vapor pressure by 10.0 torr at 35 oC. The vapor pressure of pure ethanol at 35 oC is 1.00 × 102 torr?
Q:At 63.5 oC the vapor pressure of H2O is 175At 63.5 oC the vapor pressure of H2O is 175 torr, and that of ethanol (C2H5OH) is 400 torr. A solution is made by mixing equal masses of H2O and C2H5OH.
(a) What is the mole fraction of ethanol in the solution?
(b) Assuming ideal-solution behavior, what is the vapor pressure of the solution at 63.5 oC?
(c) What is the mole fraction of ethanol in the vapor above the solution?
Q:At 20 oC the vapor pressure of benzene (C6H6) isAt 20 oC the vapor pressure of benzene (C6H6) is 75 torr, and that of toluene (C7H8) is 22 torr. Assume that benzene and toluene form an ideal solution.
(a) What is the composition in mole fractions of a solution that has a vapor pressure of 35 torr at 20 oC?
(b) What is the mole fraction of benzene in the vapor above the solution described in part (a)?
Q:(a) Why does a 0.10 m aqueous solution of NaCl(a) Why does a 0.10 m aqueous solution of NaCl have a higher boiling point than a 0.10 m aqueous solution of C6H12O6?
(b) Calculate the boiling point of each solution.
(c) The experimental boiling point of the NaCl solution is lower than that calculated, assuming that NaCl is completely dissociated in solution. Why is this the case?
Q:The structures of vitamins E and B6 are shown below.The structures of vitamins E and B6 are shown below. Predict which is largely water soluble and which is largely fat soluble. Explain.
The structures of vitamins E and B6 are shown below.Q:Arrange the following aqueous solutions, each by mass in solute,Arrange the following aqueous solutions, each by mass in solute, in order of increasing boiling point: glucose (C6H12O6), sucrose (C12H22O11), sodium nitrate (NaNO3)?
Q:List the following aqueous solutions in order of increasing boilingList the following aqueous solutions in order of increasing boiling point: 0.120 m glucose, 0.050 m LiBr, 0.050 m Zn(NO3)2?
Q:List the following aqueous solutions in order of decreasing freezingList the following aqueous solutions in order of decreasing freezing point: 0.040 m glycerin (C3H8O3), 0.020 m KBr, 0.030 m phenol (C6H5OH)?
Q:Using data from Table 13.3, calculate the freezing and boilingUsing data from Table 13.3, calculate the freezing and boiling points of each of the following solutions:
(a) 0.22 m glycerol (C3H8O3) in ethanol,
(b) 0.240 mol of naphthalene (C10H8) in 2.45 mol of chloroform,
(c) 1.50 g NaCl in 0.250 kg of water,
(d) 2.04 g KBr and 4.82 g glucose (C6H12O6) in 188 g of water?
Q:Using data from Table 13.3, calculate the freezing and boilingUsing data from Table 13.3, calculate the freezing and boiling points of each of the following solutions:
(a) 0.25 m glucose in ethanol;
(b) 20.0 g of decane, C10H22, in 50.0 g CHCl3;
(c) 3.50 g NaOH in 175 g of water,
(d) 0.45 mol ethylene glycol and 0.15 mol KBr in 150 g H2O?
Q:How many grams of ethylene glycol (C2H6O2) must added toHow many grams of ethylene glycol (C2H6O2) must added to 1.00 kg of water to produce a solution that freezes at – 5.00 oC?
Q:What is the freezing point of an aqueous solution thatWhat is the freezing point of an aqueous solution that boils at 105.0 oC?
Q:What is the osmotic pressure formed by dissolving 44.2 mgWhat is the osmotic pressure formed by dissolving 44.2 mg of aspirin (C9H8O4) in 0.358 L of water at 25 oC?
Q:Seawater contains 3.4 g of salts for every liter ofSeawater contains 3.4 g of salts for every liter of solution. Assuming that the solute consists entirely of NaCl (over 90% is), calculate the osmotic pressure of seawater at 20 oC?
Q:Adrenaline is the hormone that triggers the release of extraAdrenaline is the hormone that triggers the release of extra glucose molecules in times of stress or emergency. A solution of 0.64 g of adrenaline in 36.0 g of CCl4 elevates the boiling point by 0.49 oC. Is the molar mass of adrenaline calculated from the boiling-point elevation in agreement with the following structural formula?

Adrenaline
Q:If you wanted to prepare a solution of CO inIf you wanted to prepare a solution of CO in water at in which the CO concentration was 2.5 mM, what pressure of CO would you need to use? (See Figure 13.19.)
Q:Lauryl alcohol is obtained from coconut oil and is usedLauryl alcohol is obtained from coconut oil and is used to make detergents. A solution of 5.00 g of lauryl alcohol in 0.100 kg of benzene freezes at 4.1 oC. What is the approximate
molar mass of lauryl alcohol?
Q:Lysozyme is an enzyme that breaks bacterial cell walls. ALysozyme is an enzyme that breaks bacterial cell walls. A solution containing 0.150 g of this enzyme in 210 mL of solution has an osmotic pressure of 0.953 torr at 25 oC. What is the molar mass of lysozyme?
Q:A dilute aqueous solution of an organic compound soluble inA dilute aqueous solution of an organic compound soluble in water is formed by dissolving 2.35 g of the compound in water to form 0.250 L of solution. The resulting solution has an osmotic pressure of 0.605 atm at 25 oC. Assuming that the organic compound is a nonelectrolyte, what is its molar mass?
Q:The osmotic pressure of a 0.010 M aqueous solution ofThe osmotic pressure of a 0.010 M aqueous solution of CaCl2 is found to be 0.674 atm at 25 oC.
(a) Calculate the van’t Hoff factor, i, for the solution.
(b) How would you expect the value of i to change as the solution becomes more concentrated? Explain.
Q:Based on the data given in Table 13.4, which solutionBased on the data given in Table 13.4, which solution would give the larger freezing-point lowering, a 0.030 m solution of NaCl or a 0.020 m solution of K2SO4? How do you explain the departure from ideal behavior and the differences observed between the two salts?
Q:(a) Why is there no colloid in which both the(a) Why is there no colloid in which both the dispersed substance and the dispersing substance are gases?
Q:(a) Many proteins that remain homogeneously distributed in water have(a) Many proteins that remain homogeneously distributed in water have molecular masses in the range of 30,000 amu and larger. In what sense is it appropriate to consider such suspensions to be colloids rather than solutions? Explain.
(b) What general name is given to a colloidal dispersion of one liquid in another? What is an emulsifying agent?
Q:Indicate whether each of the following is a hydrophilic orIndicate whether each of the following is a hydrophilic or a hydrophobic colloid:
(a) Butterfat in homogenized milk,
(b) Hemoglobin in blood,
(c) Vegetable oil in a salad dressing,
(d) Colloidal gold particles in water?
Q:Explain how each of the following factors helps determine theExplain how each of the following factors helps determine the stability or instability of a colloidal dispersion:
(a) Particulate mass,
(b) Hydrophobic character,
(c) Charges on colloidal particles?
Q:Colloidal dispersions of proteins, such as a gelatin, can oftenColloidal dispersions of proteins, such as a gelatin, can often be caused to separate into two layers by addition of a solution of an electrolyte. Given that protein molecules may carry electrical charges on their outer surface as illustrated in Figure 13.30, what do you believe happens when the electrolyte solution is added?
Q:The figure shows two identical volumetric flasks containing the sameThe figure shows two identical volumetric flasks containing the same solution at two temperatures.
(a) Does the molarity of the solution change with the change in temperature? Explain.
(b) Does the molality of the solution change with the change in temperature? Explain.

Q:Explain how (a) A soap such as sodium stearate stabilizes aExplain how
(a) A soap such as sodium stearate stabilizes a colloidal dispersion of oil droplets in water;
(b) Milk curdles upon addition of an acid?
Q:Butylated hydroxytoluene (BHT) has the following molecular structure: It is widelyButylated hydroxytoluene (BHT) has the following molecular stru

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