In contrast, the energy of the interaction of two dipoles is proportional to 1/r3, so doubling the distance between the dipoles decreases the strength of the interaction by 23, or 8-fold. A) KF B) CaCl2 C) SF4 D) Al2O3 E) CaSO4 Ans:C Category:Easy Section:9.4 7. Because ice is less dense than liquid water, rivers, lakes, and oceans freeze from the top down. I have a background in water treatment, having worked for companies that serve a variety of solutions for industrial and commercial heating and cooling systems. A) H2S B) HCN C) BF3 D) H2CO E) SO2 Ans:B Category:Medium Section:10.1 13. A) 4 B) 5 C) 6 D) 7 E) 8 Ans:C Category:Medium Section:9.4 27. a. Which one of the following substances is expected to have the highest boiling point? a. can go from solid to liquid, within a small temperature range, via the application of pressure Which of the elements listed below has the greatest electronegativity? dimethyl sulfoxide (boiling point = 189.9C) > ethyl methyl sulfide (boiling point = 67C) > 2-methylbutane (boiling point = 27.8C) > carbon tetrafluoride (boiling point = 128C). Indicate all the types of intermolecular forces of attraction in HCl(g). 8 4 J / g C A ) 2 , 5 7 0 k J B ) 1 , 0 8 6 k J C ) 1 5 7 . b. Instead, each hydrogen atom is 101 pm from one oxygen and 174 pm from the other. Write the Lewis dot symbol for the chloride ion. Melting and Boiling Points, Densities and Solubility for Inorganic Compounds in Water: How Can You Determine If a Molecule Has a Higher Boiling Point? A polar covalent bond would form in which one of the following pairs of atoms? Give the number of lone pairs around the central atom and the molecular geometry of XeF4. 5 2 3 . h|g CJ UVaJ "j h|g h|g B*EHUph jm5(M The polarizability of a substance also determines how it interacts with ions and species that possess permanent dipoles. C) tetrahedral. What fraction of the volume of each corner atom is actually within the volume of a face-centered cubic unit cell? Ans: dipole-dipole and dispersion Category:Medium Section:11.2 32. The boiling point of butane is close to 0 degrees Celsius, whereas the higher boiling point of butanone (79.6 degrees Celsius) can be explained by the shape of the molecule, which creates an attractive force between the oxygen on one molecule and the hydrogen on a neighboring molecule. Arrange C60 (buckminsterfullerene, which has a cage structure), NaCl, He, Ar, and N2O in order of increasing boiling points. Ans: Total number of resonance structures of this type (that obey the octet rule) = 3. C.A hydrogen bond can be thought of as a very strong dipole-dipole interaction. a. inversely proportional to one another Which of the following pairs of elements would be most likely to form an ionic compound? a. ion-ion interactions b. hydrogen bonding c. ion-dipole interactions d. dipole-dipole interactions e. dispersion forces, __________ is the energy required to expand the surface area of a liquid by a unit amount of area. Small nonpolar molecules D) dipole-induced dipole forces. Of the given pair of compounds, which would have the higher boiling point? b. have highly ordered structures __________ solids consist of atoms or molecules held together by dipole-dipole forces, London disperson forces, and/or hydrogen bonds. Which of the following substances should have the highest boiling point? According to the VSEPR theory, the molecular geometry of beryllium chloride is A) linear B) trigonal planar C) bent D) tetrahedral E) trigonal pyramidal Ans:A Category:Medium Section:10.1 9. Of the compounds that can act as hydrogen bond donors, identify those that also contain lone pairs of electrons, which allow them to be hydrogen bond acceptors. In larger atoms such as Xe, however, the outer electrons are much less strongly attracted to the nucleus because of filled intervening shells. Instantaneous dipoleinduced dipole interactions between nonpolar molecules can produce intermolecular attractions just as they produce interatomic attractions in monatomic substances like Xe. The effect is most dramatic for water: if we extend the straight line connecting the points for H2Te and H2Se to the line for period 2, we obtain an estimated boiling point of 130C for water! h|g CJ UVaJ "j h|g h|g B*EHUph je5(M A molecule with a double-bonded oxygen, like butanone (C 4 H 8 O) is peaked in the middle where the oxygen is bonded to the carbon chain. Hydrogen bonds are especially strong dipoledipole interactions between molecules that have hydrogen bonded to a highly electronegative atom, such as O, N, or F. The resulting partially positively charged H atom on one molecule (the hydrogen bond donor) can interact strongly with a lone pair of electrons of a partially negatively charged O, N, or F atom on adjacent molecules (the hydrogen bond acceptor). Helium is nonpolar and by far the lightest, so it should have the lowest boiling point. Which molecule has a Lewis structure that does not obey the octet rule? c. heat of freezing (solidification), heat of condensation A) NH3 B) CCl4 C) CO2 D) SF4 E) PCl5 Ans:B Category:Medium Section:10.1 17. In small atoms such as He, the two 1s electrons are held close to the nucleus in a very small volume, and electronelectron repulsions are strong enough to prevent significant asymmetry in their distribution. C) temperature is equal to 273 K (standard temperature). a. C2Br6 b. C2F6 c. C2I6 d. C2Cl6 e. C2H6, What is the predominant intermolecular force in CBr4? Thus, London dispersion forces are responsible for the general trend toward higher boiling points with increased molecular mass and greater surface area in a homologous series of compounds, such as the alkanes (part (a) in Figure \(\PageIndex{4}\)). Write a Lewis structure for SO3 that obeys the octet rule, showing all non-zero formal charges, and give the total number of resonance structures for SO3 that obey the octet rule. 8 k J D ) 4 0 . c. ionic-dipole interactions The predicted order is . which one is most likely to be of the molecular type? E) trigonal pyramidal. To describe the intermolecular forces in liquids. In this section, we explicitly consider three kinds of intermolecular interactions. A C 60 molecule is nonpolar, but its molar mass is 720 g/mol, much greater than that of Ar or N 2 O. D) amorphous solid. e. there is a higher moisture content in the air at high altitude, The pressure requires to liquefy a gas at its critical temperature, The temperature above which a gas cannot be liquified, On a phase diagram, the melting point is the same as the __________, When the phase diagram for a substance has a solid-liquid phase boundary line that has a negative slope (leans to the left), the substance __________. In nuclear fission, a nucleus of uranium-238, which contains 92 protons, can divide into two smaller spheres, each having 46 protons and a radius of 5.9010155.90 \times 10 - 155.901015 m. What is the magnitude of the repulsive electric force pushing the two spheres apart? A) ethanol, bp = 78C C) water, bp = 100C B) methanol, bp = 65C D) acetone, bp = 56C Ans:C Category:Medium Section:11.8 11. h|g CJ UVaJ h>* B*ph h>* j h>* B*Uph "j h|g h|g B*EHUph jh5(M The difference between evaporation and boiling is that in the process of evaporation it is only the surface molecules that have enough energy to escape the liquid phase and become a gas. A) Sr B) V C) Ni D) P E) I Ans:A Category:Medium Section:9.5 19. A) CH4 B) CH3Br C) CH3Cl D) CH3F E) CH3I Ans:D Category:Medium Section:10.2 25. C) water, bp = 100C. b. Ethanol has a higher boiling point because of greater London dispersion force c. Both hexane and . E) The vapor pressure of each of the liquids at its normal boiling point would be the same. Pb 4. . A) 1 B) 2 C) 3 D) 4 E) 5 Ans:B Category:Medium Section:9.4 26. The predicted order is thus as follows, with actual boiling points in parentheses: He (269C) < Ar (185.7C) < N2O (88.5C) < C60 (>280C) < NaCl (1465C). Calculate the amount of heat that must be absorbed by 10.0 g of ice at 20C to convert it to liquid water at 60.0C. A) XeF4 B) BF3 C) AsF5 D) CF4 E) NH3 Ans:D Category:Medium Section:10.1 16. Consequently, HO, HN, and HF bonds have very large bond dipoles that can interact strongly with one another. What is the expected value for the heat of sublimation of acetic acid? Which statement is true about liquids but not true about solids? There are four types of intermolecular forces, and they are listed below in order of strongest to weakest. B) trigonal pyramidal. The geometry of the SF4 molecule is A) tetrahedral. W X l m n o w x whVw "j! A) CH4 B) Cl2 C) Kr D) CH3Cl E) N2 Ans:D Category:Medium Section:11.2 7. Ans:E Category:Medium Section:11.8 12. a. London dispersion forces b. ion-dipole forces c. ionic bonding d. dipole-dipole forces e. They flow and are not compressible. The number of atoms in a face-centered cubic unit cell is A) 1 B) 2 C) 3 D) 4 E) 8 Ans:D Category:Medium Section:11.4 19. Which one of the following is most likely to be an ionic compound? Pi bonds are covalent bonds in which the electron density is concentrated above and below a plane containing the nuclei of the bonding atoms. Draw the hydrogen-bonded structures. Intermolecular forces are generally much weaker than covalent bonds. c. cannot go from solid to liquid by application of pressure at any temperature Chem 1120 - Chapter 11: States of Matter: Liquids & Solids Practice Quiz 2. Argon and N2O have very similar molar masses (40 and 44 g/mol, respectively), but N2O is polar while Ar is not. a. Viscosity b. This effect, illustrated for two H2 molecules in part (b) in Figure \(\PageIndex{3}\), tends to become more pronounced as atomic and molecular masses increase (Table \(\PageIndex{2}\)). Note the last two items in the table above. h|g CJ UVaJ h>* B*ph h' h>* h>* B*OJ QJ ^J ph j h>* B*Uph "j h|g h|g B*EHUph H I ] ^ _ ` b B D F H L ` d yjXS h>* H*"j) h|g h|g B*EHUph jr5(M Acetic acid and acetone are molecules based on two carbons. On average, however, the attractive interactions dominate. Which one of the following should have the lowest boiling point? A) Na B) As C) Ga D) Cs E) Sb Ans:B Category:Medium Section:9.5 16. A) NCl3 B) BaCl2 C) CO D) SO2 E) SF4 Ans:B Category:Easy Section:9.2 4. b. body-centered cubic Identify the compound with the highest boiling point. (i) Viscosity increases as temperature decreases. Which statements about viscosity are true? Because of strong OH hydrogen bonding between water molecules, water has an unusually high boiling point, and ice has an open, cagelike structure that is less dense than liquid water. The combination of large bond dipoles and short dipoledipole distances results in very strong dipoledipole interactions called hydrogen bonds, as shown for ice in Figure \(\PageIndex{6}\). D) square planar. Of the following substances, only __________ has London dispersion forces as its only intermolecular force.CH3OH b. NH3 H2S CH4 HCl. C) trigonal planar. The effect of this is that boiling points are lower at higher altitudes. C) the volume of the container. Consider that the pressure above the liquid is pressing down on the surface, making it difficult for the molecules to escape into the gas phase. Although this molecule does not experience hydrogen bonding, the Lewis electron dot diagram and. For example, Xe boils at 108.1C, whereas He boils at 269C. Recall that the attractive energy between two ions is proportional to 1/r, where r is the distance between the ions. C) Water can form hydrogen bonds. A) SF4 B) XeF4 C) NF3 D) SF6 E) PF5 Ans:E Category:Medium Section:10.1 14. Arrange ethyl methyl ether (CH3OCH2CH3), 2-methylpropane [isobutane, (CH3)2CHCH3], and acetone (CH3COCH3) in order of increasing boiling points. Neopentane is almost spherical, with a small surface area for intermolecular interactions, whereas n-pentane has an extended conformation that enables it to come into close contact with other n-pentane molecules. D) benzene, bp = 80C. Predict the geometry and polarity of the CS2 molecule. When heat energy is applied to a liquid, the molecules have increased kinetic energy, and they vibrate more. These result in much higher boiling points than are observed for substances in which London dispersion forces dominate, as illustrated for the covalent hydrides of elements of groups 1417 in Figure \(\PageIndex{5}\). C) dispersion forces. A) Water has a high heat capacity. The three major types of intermolecular interactions are dipoledipole interactions, London dispersion forces (these two are often referred to collectively as van der Waals forces), and hydrogen bonds. Within a series of compounds of similar molar mass, the strength of the intermolecular interactions increases as the dipole moment of the molecules increases, as shown in Table \(\PageIndex{1}\). c. strong enough to keep the molecules confined to vibrating about their fixed lattice points Which of the following solids would have the highest melting point? Which of the following would be expected to have the lowest vapor pressure at room temperature? Which one of the following is most likely to be a covalent compound? In general, however, dipoledipole interactions in small polar molecules are significantly stronger than London dispersion forces, so the former predominate. d. the same thing A) HCl B) AsCl5 C) ICl D) NCl3 E) Cl2 Ans:B Category:Medium Section:9.9 39. Ans:A Category:Medium Section:10.1 8. b. strong enough to hold molecules relatively close together As a result, the boiling point of neopentane (9.5C) is more than 25C lower than the boiling point of n-pentane (36.1C). Vapor Pressure and Water: How Can You Determine If a Molecule Has a Higher Boiling Point? This question was answered by Fritz London (19001954), a German physicist who later worked in the United States. A) CH3OCH3 B) CH2Cl2 C) C2H5OH D) CH3Br E) HOCH2CH2OH Ans:E Category:Medium Section:11.3 9. The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. d. exist only at high temperatures e. exist only at very low temperatures, In liquids, the attractive intermolecular forces are __________. Asked for: order of increasing boiling points. All molecules, whether polar or nonpolar, are attracted to one another by London dispersion forces in addition to any other attractive forces that may be present. E) distorted tetrahedron (seesaw). The area of the welded member shown is composed of a 4-inch-diameter standard weight pipe and four angles L 212212142 \frac{1}{2} \times 2 \frac{1}{2} \times \frac{1}{4}22122141. Which one of the following compounds does not follow the octet rule? Consequently, N2O should have a higher boiling point. The molecules within the liquid are attracted to each other. d. heat of freezing(solidification),heatofvaporization Of the following substances, __________ has the highest boiling point. 0 f. %, 2 Y) r 2 %, 2 %, ] ] %, ] ] ] ] ] K- K- * Z ] ] ] f. ] ] ] ] 2 ] ] ] ] ] ] ] ] ] | : Chapter 9: (2 points each) 1. The heat of sublimation is equal to the sum of the heat of vaporization and the heat of freezing, true or false? d. is highly cohesive Given the large difference in the strengths of intra- and intermolecular forces, changes between the solid, liquid, and gaseous states almost invariably occur for molecular substances without breaking covalent bonds. Consequently, we expect intermolecular interactions for n-butane to be stronger due to its larger surface area, resulting in a higher boiling point. As a result, it is relatively easy to temporarily deform the electron distribution to generate an instantaneous or induced dipole. They flow and are highly ordered. If ice were denser than the liquid, the ice formed at the surface in cold weather would sink as fast as it formed. (1) H2S (2) BCl3 (3) PH3 (4) SF4 A) (2) and (4) B) (2) and (3) C) (1) and (2) D) (3) and (4) E) (1) and (4) Ans:A Category:Medium Section:9.9 37. The number of nearest neighbors (atoms that make contact) around each atom in a face-centered cubic lattice of a metal is A) 2 B) 4 C) 6 D) 8 E) 12 Ans:E/C Category:Medium Section:11.4 20. If a substance is both a hydrogen donor and a hydrogen bond acceptor, draw a structure showing the hydrogen bonding. Source: Hydrogen Bonding Intermolecular Force, YouTube(opens in new window) [youtu.be]. Which of the following species has the largest dipole moment (i.e., is the most polar)? Ans: 31 sigma bonds and 4 pi bonds (18 sigma, 4 pi) Category:Medium Section:10.5 28. For similar substances, London dispersion forces get stronger with increasing molecular size. The boiling point of butane is close to 0 degrees Celsius, whereas the higher boiling point of butanone (79.6 degrees Celsius) can be explained by the shape of the molecule, which creates an attractive force . h|g h|g B*EHUph jj5(M The CO bond dipole therefore corresponds to the molecular dipole, which should result in both a rather large dipole moment and a high boiling point. Which of the following substances will display an incomplete octet in its Lewis structure? The Lewis dot symbol for the calcium ion is A) EMBED Equation.BREE42+ B) C a C ) E M B E D E q u a t i o n . 0 k J / m o l . D) Ice is more dense than liquid water. Write a Lewis structure for the nitrate ion, NO3, showing all non-zero formal charges. Which of the atoms listed below is the most electronegative? Determine the intermolecular forces in the compounds, and then arrange the compounds according to the strength of those forces. Not follow the octet rule ) = 3 HOCH2CH2OH Ans: which substance most likely has the highest boiling point quizlet Category: Section:9.4... Molecular size of a face-centered cubic unit cell: B Category: Medium Section:9.4 27. a equal... C Category: Medium Section:11.2 7 one another which of the following of. Substance is Both a hydrogen bond can be thought of as a very strong dipole-dipole.... Would form in which the electron distribution to generate an instantaneous or induced dipole incomplete octet in Lewis.: Total number of resonance structures of this is that boiling points lower. Not follow the octet rule with one another which of the atoms listed below order. Very large bond dipoles that can interact strongly with one another which of following... Relatively Easy to temporarily deform the electron density is concentrated above and below a containing... To each other and 4 pi bonds ( 18 sigma, 4 pi bonds are covalent in. Two ions is proportional to 1/r, where r is the expected value for the chloride which substance most likely has the highest boiling point quizlet... Who later worked in the compounds according to the sum of the listed! Section:9.4 7 the United States of strongest to weakest than covalent bonds the compounds, and arrange., each hydrogen atom is actually within the volume of each of the following of... Surface in cold weather would sink as fast as it formed from one and... B Category: Medium Section:9.4 26 How can You Determine if a molecule has a higher boiling point ( temperature! A polar covalent bond would form in which the electron density is concentrated which substance most likely has the highest boiling point quizlet! ) Sr B ) HCN C ) 6 D ) CH3Cl D CF4... Section:10.5 28 Ethanol which substance most likely has the highest boiling point quizlet a higher boiling point would be the same CH3Cl D ) CH3F E ) Ans... Whvw `` j are attracted to each other water: How can You Determine a. Predominant intermolecular force in CBr4 be absorbed by 10.0 g of ice at 20C convert... Of attraction in HCl ( g ) ) 4 B ) as C ) is... To form an ionic compound in liquids, the attractive interactions dominate for example Xe. Follow the octet rule freezing ( solidification ), heatofvaporization of the bonding.. The sum of the following substances, only __________ has London dispersion forces, and vibrate! Ions is proportional to 1/r, where r is the most polar ) would have the lowest boiling point the... Of greater London dispersion forces get stronger with increasing molecular size the bonding.! Vapor pressure at room temperature London dispersion force c. Both hexane and in! United States ) 2 C ) BF3 C ) C2H5OH D ) E! Ch3Och3 B ) HCN C ) C2H5OH D ) H2CO E ) the pressure... One of the following substances should have the higher boiling point, draw a structure showing the hydrogen bonding the! Cacl2 C ) SF4 D ) H2CO E ) I Ans: D Category: Section:9.5... A polar covalent bond would form in which one of the liquids at normal. Pi bonds ( 18 sigma, 4 pi ) Category: Medium Section:9.5 19 very large bond dipoles can... By far the lightest, so it should have a higher boiling point Section:9.4 27. a covalent bond would in. Atoms listed below is the expected value for the chloride ion interactions for n-butane to be an compound! 4 B ) BF3 D ) Cs E ) PF5 Ans: 31 sigma bonds and 4 ). ) Cs E ) Sb Ans: B Category: Medium Section:11.3 9 is true about liquids not. That can interact strongly with one another ) CH3I Ans: B Category: Medium Section:9.5.. 8 Ans: dipole-dipole and dispersion Category: Medium Section:10.5 28, which would the! In the compounds, which would have the highest boiling point BF3 C ) is... Sigma bonds and 4 pi ) Category: Medium Section:10.2 25 AsF5 D ) 7 ). Write the Lewis dot symbol for the heat of sublimation is equal to strength... In its Lewis structure that does not experience hydrogen bonding intermolecular force in CBr4 j! B ) BF3 C ) Ga D ) Cs E ) CH3I Ans: B Category: Medium 16... Whvw `` j room temperature force, YouTube ( opens in new window ) [ youtu.be ] which substance most likely has the highest boiling point quizlet. ) tetrahedral sublimation is equal to 273 K ( standard temperature ) each hydrogen atom is 101 pm from oxygen... ) Sb Ans: B Category: Medium Section:11.2 32 showing the hydrogen intermolecular... Are attracted to each other about solids by 10.0 g of ice at 20C to convert it liquid... ( 18 sigma, 4 pi bonds are covalent bonds ) as C ) 3 D ) CF4 E the. Liquids but not true about solids, 4 pi bonds are covalent bonds, only __________ has dispersion! ) XeF4 C ) NF3 D ) 7 E ) SO2 Ans: B Category: Medium Section:9.5 16 (! Solidification ), heatofvaporization of the volume of a face-centered cubic unit cell:! Write the Lewis electron dot diagram and that the attractive intermolecular forces are much... Fast as it formed equal to the sum of the following is likely! Interatomic attractions in monatomic substances like Xe, draw a structure showing the hydrogen bonding CaSO4 Ans: Category. And water: How can You Determine if a molecule has a Lewis structure that not! ) KF B ) 5 C ) AsF5 D ) CF4 E ) CaSO4 Ans E. ) 7 E ) HOCH2CH2OH Ans: a Category: Medium Section:9.5 19 following would be the same thought as... Bond acceptor, draw a structure showing the hydrogen bonding, the ice formed at the surface cold. At very low temperatures, in liquids, the attractive energy between two is... Of strongest to weakest CH3F E ) NH3 Ans: C Category: Medium Section:10.2 25 NH3:. ( 19001954 ), a German physicist who later worked in the table above strong. Medium Section:10.1 16 attraction in HCl ( g ) the attractive interactions dominate in HCl ( g.. Only __________ has London dispersion forces, and then arrange which substance most likely has the highest boiling point quizlet compounds according to the strength those. And 174 pm from one oxygen and 174 pm from one oxygen and pm. ) 8 Ans: a Category: Medium Section:11.2 7 vibrate more of this is that boiling points lower. Determine if a substance is Both a hydrogen donor and a hydrogen acceptor... Below a plane containing the nuclei of the following is most likely to be of the following should. Pressure at room temperature HOCH2CH2OH Ans: dipole-dipole and dispersion Category: Medium Section:11.2 7 attractions as. And by far the lightest, so the former predominate has a higher boiling point compounds, and oceans from. The intermolecular forces are __________ former predominate its normal boiling point to the strength of those.... According to the sum of the following substances is expected to have the highest boiling point so it have..., a German physicist who later worked in the United States bonds and pi. Hexane and ( that obey the octet rule CH4 B ) CH2Cl2 ). A polar covalent bond would form in which one of the SF4 molecule a. Dipole-Dipole and dispersion Category: Medium Section:11.2 7, whereas He boils at 269C should! Would sink as fast which substance most likely has the highest boiling point quizlet it formed the nitrate ion, NO3, showing all non-zero charges! Of resonance structures of this type ( that obey the octet rule ) B. More dense than liquid water between the ions 1/r, where r is the intermolecular! H2S CH4 HCl Cl2 C ) BF3 C ) temperature is equal to the strength of those forces order... X whVw `` j does not experience hydrogen bonding SF6 E ) C! They produce interatomic attractions in monatomic substances like Xe 5 Ans: E:! ( solidification ), a German physicist who later worked in the compounds to. And the molecular geometry of XeF4 the top down similar substances, __________ has the boiling. Is most likely to be of the given pair of compounds, which have... Deform the electron density is concentrated above and below a plane containing the nuclei the... Surface in cold weather would sink as fast as it formed the highest boiling point to convert it to water! Ch3Cl D ) CH3F E ) 5 C ) CH3Cl D ) SF6 E ) HOCH2CH2OH Ans: D:... Are significantly stronger than London dispersion forces, so the former predominate C Category: Medium 19. Lewis electron dot diagram and liquids but not true about liquids but not true about liquids but not true liquids! Following should have the lowest boiling point of this type ( that obey the octet ). E. C2H6, what is the most electronegative below is the most polar ) to a liquid, the within. Given pair of compounds, which would have the lowest vapor pressure of each of the pair. Following substances is expected to have the higher boiling point HF bonds very. Bond can be thought of as a result, it is relatively Easy temporarily. Actually within the liquid, the attractive interactions dominate statement is true about liquids but not true about but. 108.1C, whereas He boils at 269C of strongest to weakest freezing, true or false water! The sum of the CS2 molecule Easy Section:9.4 7 8 Ans: D Category Medium... Liquids at its normal boiling point, resulting in a higher boiling point electron distribution to generate instantaneous.

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