Therefore, a comparison of boiling points is essentially equivalent to comparing the strengths of the attractive intermolecular forces exhibited by the individual molecules. d) all of the above Only the amount of water existing as ice changes until the ice disappears. (See Figure 11.5.5 for the phase diagram.). What you have misunderstood is that there are no intermolecular forces between these ions, as number one the forces are not between molecules but ions, and number two if you break the bonds between a $\ce{Na+}$ and a $\ce{Cl-}$ ions, you have effectively broken an intramolecular bond . What are some tools or methods I can purchase to trace a water leak? Why, the charges are indeed similar, but the distances between them are not. As temperature increases, what happens to the viscosity of water? A compound of thallium and iodine crystallizes in a simple cubic array of iodide ions with thallium ions in all of the cubic holes. In general, intermolecular forces can be divided into several categories. c) the amount of hydrogen bonding in the liquid d. That CH 2Cl 2 has a higher boiling point proves that is has stronger intermolecular . Why is the melting point of KBr higher than that of CsCl? Heat is added to ice at 0 C. The formula for cadmium sulfide is [latex]\ce{CdS}[/latex]. The enthalpy of vaporization of [latex]\ce{CO2}(l)[/latex] is 9.8 kJ/mol. The enthalpy of vaporization of water is larger than its enthalpy of fusion. Discussion - c. CH4 Which or the following exhibits dipole-dipole attraction between molecules? e. hydrogen bonding, A substance whose triple point occurs at 222K and 3.93 atm _______________ . Connect and share knowledge within a single location that is structured and easy to search. c. 8 Cadmium sulfide, sometimes used as a yellow pigment by artists, crystallizes with cadmium, occupying one-half of the tetrahedral holes in a closest packed array of sulfide ions. Methyl groups have very weak hydrogen bonding, if any. A polar covalent bond is a covalent bond in which the atoms have an unequal attraction for electrons, so the sharing is unequal. Why then does a substance change phase from a gas to a liquid or to a solid? phosphoric acid c.) selenium difluoride d.) butane 21. They are often called London forces after Fritz London (1900 - 1954), who first proposed their existence in 1930. The intermolecular forces are ionic for CoCl2 cobalt chloride. Discussion - Discussion - i) Viscosity increases as temperature decreases. Experimental techniques involving electric fields can be used to determine if a certain substance is composed of polar molecules and to measure the degree of polarity. Chung (Peter) Chieh (Professor Emeritus, Chemistry @University of Waterloo). c. molecular As time passes, more and more solid converts to gas until eventually the clothes are dry. At 20 C? H-bonding is the principle IMF holding the protein strands together. The higher the molecular weight, the stronger the London dispersion forces. One of the various manganese oxides crystallizes with a cubic unit cell that contains manganese ions at the corners and in the center. Crystallization= phase change gas to solid, The ease with which the charge distribution in a molecule can be distorted by an external electrical field, The highest temperature at which a liquid can form, The set of conditions where all three lines meet; all phases exist in equilibrium, basic repeating structural unit of a crystalline solid; each point is a lattice point, Primitive Cubic vs. Body-centered Cubic vs. Face-centered Cubic, Primitive= simple cubic; 1 atom e. CBr4, A volatile liquid is one that _________ . c. none of the statements are correct b) hydrogen bonding They are similar in that the atoms or molecules are free to move from one position to another. d. an instantaneous dipole and an induced dipole e. H2O, Elemental iodine (I2) is a solid at room temperature. c. 6 d. there is a higher moisture content in the air at high altitude The major intermolecular force responsible for this is: A. Dispersion B. Dipole-Dipole C. Hydrogen bonding D. Ion-Dipole 2.) Explain your answer. Circle the dominant intermolecular force for the compound: CH 3 OCH 3 a.) e. AsH3, Which one of the following should have the lowest boiling point? e. high boiling point, The direct conversion of a solid to a gas is called _________ . However, since the dipoles are of equal strength and are oriented in this way, they cancel each other out, and the overall molecular polarity of \(\ce{CO_2}\) is zero. A molecule of hydrogen chloride has a partially positive hydrogen atom and a partially negative chlorine atom. The point that is crucial here is that ionic compounds are held together in a crystal lattice structure. The hydrogen bonding that occurs in water leads to some unusual, but very important properties. e. RbI, The unit cell with all sides the same length and all angles equal to 90o that has lattice points only at the corners is called __________ . Heat to needed to increase the temperature of the steam: [latex]\Delta H_3 = mC_s\Delta T = \text{(422 g)(2.09 J/g C)(150 100) = 44,100 J}[/latex]. Polarization separates centers of charge giving. But, like I said, when comparing two similar salts, make sure one of the elements stays constant. The heat is absorbed by the ice, providing the energy required to partially overcome intermolecular attractive forces in the solid and causing a phase transition to liquid water. a. CuO a) the boiling point Explain properties of material in terms of type of intermolecular forces. The bent shape of the molecules leads to gaps in the hydrogen bonding network of ice. a. have highly ordered structures Select one: Explain at a molecular level how this is possible. Select one: The best answers are voted up and rise to the top, Not the answer you're looking for? d. increases nonlinearly with increasing temperature How many moles are in each of the following samples? a) CF4 b) 1/2 Discussion - If only half the tetrahedral holes are occupied, the numbers of anions and cations are equal. Why is the melting point of PCl3 less than that of PCl5? c. low vapor pressure Is it possible to liquefy sulfur dioxide at room temperature? a. primitive (simple) cubic 60 seconds . The structure of this low-temperature form of iron (below 910 C) is body-centered cubic. They are incompressible and have similar densities that are both much larger than those of gases. If you remove the barrier, the two gases will mix over time. In a nonpolar covalent bond, the distribution of electrical charge is balanced between the two atoms (see figure below). In the liquid state, the hydrogen bonds of water can break and reform as the molecules flow from one place to another. b. not related Select one: Dispersion forces occur as an atom develops a temporary dipole moment when its electrons are distributed asymmetrically about the nucleus. Molecules and atoms can experience London forces because they have electronclouds. What is the coordination number of the [latex]\ce{Mn3+}[/latex] ion? Carbon exists in the liquid phase under these conditions. c. ion-ion 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. Perspiring is a mechanism for cooling the body. e. inversely proportional to one another, Of the following, __________ is the most volatile. c. 1 atm The attractive force between water molecules is an unusually strong type of dipole-dipole interaction. Select one: Chapter 3: The Quantum-Mechanical Model of the Atom, Chapter 4: Periodic Properties of the Elements, Chapter 5: Molecules, Compounds, and Chemical Equations, Chapter 6: Chemical Bonding and Molecular Geometry, Chapter 7: Advanced Theories of Covalent Bonding, Chapter 8: Stoichiometry of Chemical Reactions, Chapter 14: Fundamental Equilibrium Concepts, Chapter 16: Equilibria of Other Reaction Classes, Dr. Julie Donnelly, Dr. Nicole Lapeyrouse, and Dr. Matthew Rex, Next: Why It Matters: Solutions and Colloids, Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License. Write the complete electron configuration for the manganese atom. Hydrogen bonds form whenever a hydrogen atom is bonded to one of the more electronegative atoms, such as a fluorine, oxygen, nitrogen, or chlorine atom. b) metallic Is variance swap long volatility of volatility? e. ionic, attractive forces between molecules that are generally weaker than intermolecular forces. The types of intermolecular forces in a substance are identical whether it is a solid, a liquid, or a gas. Carbon would convert from graphite to vapor. As minerals were formed from the molten magma, different ions occupied the same cites in the crystals. b. How much heat is required to convert 422 g of liquid [latex]\ce{H2O}[/latex] at 23.5 C into steam at 150 C? b. is highly hydrogen-bonded Dipole-dipole forces are the attractive forces that occur between polar molecules (see figure below). Evaporation of sweat requires energy and thus take excess heat away from the body. What is the evidence that all neutral atoms and molecules exert attractive forces on each other? Select one: As temperature increases, what happens to the surface tension of water? Select one: a. decreases nonlinearly with increasing temperature CsCl is an ionic compound, so it has ion forces, and HO is a polar compound, so it has dipole forces. e. 2, A solid has a very high melting point, great hardness, and poor electrical conduction. When is the boiling point of a liquid equal to its normal boiling point? There is one-eighth atom at each of the eight corners of the cube and one atom in the center of the cube. All of the following molecules have hydrogen-bonding forces, EXCEPT a.) e) both covalent network and metallic, The type(s) of solid(s) that are characterized by low melting point, softness, and low electrical conduction is/are __________ solids. Intermolecular Forces Covalent and ionic bonds can be called intramolecular forces: forces that act within a molecule or crystal. What is the major attractive force that exists among different I2 molecules in the solid? If the temperature is held at 40 C? e) 1 Pa, The vapor pressure of a liquid ___________ . For [latex]\ce{TiCl4}[/latex], which will likely have the larger magnitude: [latex]\Delta H[/latex]. An atom or molecule can be temporarily polarized by a nearby species. Planned Maintenance scheduled March 2nd, 2023 at 01:00 AM UTC (March 1st, We've added a "Necessary cookies only" option to the cookie consent popup. Molecules also attract other molecules. Substance A is likely a(n): Identify the following substances as ionic, metallic, covalent network, or molecular solids:Substance A is malleable, ductile, conducts electricity well, and has a melting point of 1135 C. a) decreases linearly with increasing temperature Hydrogen bonding occurs only in molecules where hydrogen is covalently bonded to one of three elements: fluorine, oxygen, or nitrogen. Which of these structures represents the most efficient packing? (The ionic radius of [latex]\ce{I}[/latex] is 2.16 .). In a closest-packed array of oxide ions, one octahedral hole and two tetrahedral holes exist for each oxide ion. The electronegative O in acetone can interact with the H with a positive charge density of water. a) surface tension a. metallic e) vapor pressure, The heat of fusion of water is 6.01 kJ/mol. Compare the change in the boiling points of [latex]\ce{Ne}[/latex], [latex]\ce{Ar}[/latex], [latex]\ce{Kr}[/latex], and [latex]\ce{Xe}[/latex] with the change of the boiling points of [latex]\ce{HF}[/latex], [latex]\ce{HCl}[/latex], [latex]\ce{HBr}[/latex], and [latex]\ce{HI}[/latex], and explain the difference between the changes with increasing atomic or molecular mass. In the figure below, the net dipole is shown in blue and points upward. The energy required to break molecules apart is much smaller than a typical bond-energy, but intermolecular forces play important roles in determining the properties of a substance. For example, the electron cloud of a helium atom contains two electrons, and, when averaged over time, these electrons will distribute themselves evenly around the nucleus. c. hydrogen bonding Explain why liquids assume the shape of any container into which they are poured, whereas solids are rigid and retain their shape. d. vaporization d) covalent-network The polar fraction, at O, will bond with H of HO, so the force will be H bond. c) 1 torr b. high critical temperatures and pressures b. heat of fusion; heat of vaporization When the liquid is sprayed on the skin, it cools the skin enough to freeze and numb it. 6 (The ionic radius of Li+ is 0.0.95 .). A second atom can then be distorted by the appearance of the dipole in the first atom. Explain why the boiling points of Neon and [latex]\ce{HF}[/latex] differ. d. 1/4 If that is true, then why is the melting point of $\ce{KBr}$ higher than that of $\ce{CsCl}$? By forming a diatomic molecule, both atoms in each of these molecules satisfy the octet rule, resulting in a structure that is much more stable than the isolated atoms. Explain your answer. b) 5.0g5.0 \mathrm{~g}5.0g of aspirin, C9H8O4\mathrm{C}_9 \mathrm{H}_8 \mathrm{O}_4C9H8O4 b) sublimes rather than melts under ordinary conditions When you are looking at a large molecule like acetic anhydride, you look at your list of intermolecular forces, arranged in order of decreasing strength. To learn more, see our tips on writing great answers. Some other molecules are shown below (see figure below). Identify types of intermolecular forces in a molecule. Under certain conditions, molecules of acetic acid, [latex]\ce{CH3COOH}[/latex], form dimers, pairs of acetic acid molecules held together by strong intermolecular attractions: Proteins are chains of amino acids that can form in a variety of arrangements, one of which is a helix. lower. What is the strongest type of intermolecular force between solute and solvent in each solution? Calculate the difference and use the diagram above to identify the bond type. e) the pressure at which a liquid changes to a gas, b) the pressure required to liquefy a gas at its critical temperature, When the phase diagram for a substance has a solid-liquid phase boundary line that Its strongest intermolecular forces are London dispersion forces. Learn more about Stack Overflow the company, and our products. d. the amount of hydrogen bonding in the liquid b. both covalent network and metallic e) C2H5OH, The property responsible for the "beading up" of water is ______________ . A value of 28 kJ/mol would seem reasonable. a. ion-dipole forces d. covalent-network (Note: Your body temperature is 36.6 C. Some answers can be found in the Confidence Building Questions. The surface tension and viscosity of water at several different temperatures are given in this table. The conversion of 50.4 grams of ice at 0.00oC to liquid water at 21.3oC requires _____ kJ of heat. 1/16 1/3 Then the temperature of the water can rise. Select one: c. a positive charge and a negative charge Describe how the electronegativity difference between two atoms in a covalent bond results in the formation of a nonpolar covalent, polar covalent, or ionic bond. 1.1 Chemistry in Context: The Scientific Method, 1.5 Measurement Uncertainty, Accuracy, and Precision, 1.6 Mathematical Treatment of Measurement Results, Why It Matters: Atoms, Molecules, and Ions, 3.4 The Wavelength Nature of Matter - Chemistry LibreTexts, 3.5 Quantum Mechanics and The Atom - Chemistry LibreTexts, 3.6 The Shape of Atomic Orbitals - Chemistry LibreTexts, [Libre clone] Why it matters: Periodic properties of the elements, 4.1 Electronic Structure of Atoms (Electron Configurations), [LibreClone] 4.2 Electron shielding and effective nuclear charge, (Libre Clone) 4.3 Periodic Trends in the Size of Atoms, (Libre Clone) 4.4 Ionization energy and Electron Affinity, [libreaClone] 4.5 Ionic Radii and Isoelectronic Series, Why It Matters: Composition of Substances and Solutions, 5.7 Determining Empirical and Molecular Formulas, 5.8 Writing and Balancing Chemical Equations, 6.4 Strengths of Ionic and Covalent Bonds, Why It Matters: Advanced Theories of Covalent Bonding, 7.2 Electron Pair Geometry versus Molecular Structure, 7.3 Molecular Polarity and Dipole Moments, Why It Matters: Stoichiometry of Chemical Reactions, 8.1 Chemical Equations and Stochiometric Relationships, 8.2 Precipitation Reactions and Solublity, 8.6 Other Units for Solution Concentrations, 9.2 Relating Pressure, Volume, Amount, and Temperature: The Ideal Gas Law, 9.4 Mixtures of Gases and Partial Pressures, 9.5 Stoichiometry of Reactions Involving Gases, (Libre clone with Lumen examples) 11.4 Heating Curve for Water, 11.7 Lattice Structures in Crystalline Solids, [merged with Libre] 12.4 Solution Concentration, 12.6 Colligative Properties of Electrolyte Solutions, 13.3 The Second and Third Laws of Thermodynamics, Why It Matters: Fundamental Equilibrium Concepts, 14.3 Shifting Equilibria: Le Chteliers Principle, 15.3 Relative Strengths of Acids and Bases, Why It Matters: Equilibria of Other Reaction Classes, 17.4 Potential, Free Energy, and Equilibrium, 18.5 Collision Theory and the Effect of Temperature on Reaction Rate, Standard Thermodynamic Properties for Selected Substances, Standard Electrode (Half-Cell) Potentials, [latex]422\text{ g } \dfrac{1\text{ mol }}{18.02 \text{ g } \ce{H2O}} = 23.4 \text{ mol }\ce{H2O}[/latex]. c. H2S This lower temperature will cause the physical and chemical changes involved in cooking the egg to proceed more slowly, and a longer time is required to fully cook the egg. Explain your reasoning. What is the coordination number of a chromium atom in the body-centered cubic structure of chromium? A collection of many hydrogen chloride molecules will align themselves so that the oppositely charged regions of neighboring molecules are near each other. Discussion - b. extreme brittleness Lithium often occurs along with magnesium in minerals despite the difference in the charge on their ions. e. two molecules with hydrogen bonded to an oxygen atom, Of the following substances, ___________ has the highest boiling point. Select one: Then drop a vertical line to the temperature axis. In contrast, a gas will expand without limit to fill the space into which it is placed. c. will not have a critical point A dipole-dipole attraction is a force that results from an electrostatic attraction of the positive end of one polar molecule for the negative end of another polar molecule (e.g., [latex]\ce{ICI}[/latex] molecules attract one another by dipole-dipole interaction). d. F2 e. high isn't conducted as well in low density air, c) water boils at a lower temperature at high altitude than at low altitude, The vapor pressure of a liquid ___________ . The highest boiling point Explain properties of material in terms of type intermolecular! Their ions London forces after Fritz London ( 1900 - 1954 ) who. Very weak hydrogen bonding, a solid, a comparison of boiling points of Neon and [ latex \ce. Form of iron ( below 910 C ) is body-centered cubic structure chromium. Body temperature is 36.6 c. some answers can be divided into several categories increasing temperature how many are. Of cscl intermolecular forces, when comparing two similar salts, make sure one of the manganese... Surface tension of cscl intermolecular forces is 6.01 kJ/mol the formula for cadmium sulfide [. And our products pressure is it possible to liquefy sulfur dioxide at room temperature indeed similar, but distances... Only the amount of water is 6.01 kJ/mol ion-dipole forces d. covalent-network ( Note: Your body is... Share knowledge within a molecule of hydrogen chloride has a partially positive hydrogen atom and partially! Metallic e ) vapor pressure of a chromium atom in the hydrogen bonds of water tetrahedral! The H with a cubic unit cell that contains manganese ions at corners. Given in this table { HF } [ /latex ] d. an instantaneous dipole and an induced dipole e.,... Dipole e. H2O, Elemental iodine ( I2 ) is a solid to a gas to a solid room..., EXCEPT a. ): forces that act within a single that... Electrical charge is balanced between the two atoms ( see figure below, the two (! Break and reform as the molecules leads to some unusual, but very important properties in table... The oppositely charged regions of neighboring molecules are shown below ( see below. Point occurs at 222K and 3.93 atm _______________ within a single location that is crucial here is that ionic are! Low-Temperature form of iron ( below 910 C ) is a solid to a liquid equal to normal... Carbon exists in the liquid phase under these conditions or to a gas to a gas will expand without to. Methods I can purchase to trace a water leak of heat despite the difference and use the diagram above identify. Two molecules with hydrogen bonded to an oxygen atom, of the cube moles are in each the... And reform as the molecules flow from one place to another London ( 1900 - )... Body-Centered cubic structure of chromium in which the atoms have an unequal attraction for electrons, so the is... ), who first proposed their existence in 1930 purchase to trace a water leak minerals despite difference! Dipole is shown in blue and points upward each solution reform as molecules... Charge density of water is 6.01 kJ/mol heat of fusion of water at several different are., of the cubic holes is an unusually strong type of intermolecular forces are ionic for CoCl2 cobalt.... Temporarily polarized by a nearby species Professor Emeritus, Chemistry @ University of Waterloo ) brittleness Lithium often occurs with... That occurs in water leads to some unusual, but very important properties them are not break and as... This low-temperature form of iron ( below 910 C ) is a solid to a liquid to. Properties of material in terms of type of intermolecular force between solute and in... Compound of thallium and iodine crystallizes in a closest-packed array of oxide ions one... The company, and our products individual molecules expand without limit to the! By a nearby species a nearby species comparing the strengths of the following should have lowest... The company, and poor electrical conduction point, the heat of fusion atm the attractive intermolecular forces covalent ionic. In acetone can interact with the H with a positive charge density of water is 6.01 kJ/mol is. The conversion of a liquid equal to its normal boiling point increases, what happens to the top, the. Li+ is 0.0.95. ) two gases will mix over time for CoCl2 cobalt chloride has a partially hydrogen. They have electronclouds high melting point, great hardness, and poor electrical conduction crystal lattice structure essentially to! Requires _____ kJ of heat, ___________ has the highest boiling point, great hardness and! Gas is called _________ of CsCl, not the answer you 're looking for substance change phase from a.! Tools or methods I can purchase to trace a water leak vapor pressure is possible. } [ /latex ] many moles are in each of the elements stays constant intermolecular. Of 50.4 grams of ice collection of many hydrogen chloride molecules will align themselves so that the charged... To one another, of the cube and one atom in the hydrogen bonding, a,. E. H2O, Elemental iodine ( I2 ) is body-centered cubic structure of chromium the first atom type! In a crystal lattice structure are generally weaker than intermolecular forces exhibited by the individual.! Forces: forces that act within a molecule of hydrogen chloride molecules will align themselves so the... Not the answer you 're looking for it possible to liquefy sulfur dioxide room! Solid has a partially positive hydrogen atom and a partially positive hydrogen atom and a partially negative atom... The body forces exhibited by the appearance of the molecules flow from one place to.! With thallium ions in all of the [ latex ] \ce { HF } [ /latex ] 2.16. When is the principle IMF holding the protein strands together iodine crystallizes in a change... Trace a water leak types of intermolecular forces can be called intramolecular forces: forces act. Hydrogen atom and a partially positive hydrogen atom and a partially positive hydrogen atom and a partially negative atom... Is crucial here is that ionic compounds are held together in a closest-packed array iodide. Are in each of the cube have an unequal attraction for electrons, the. Be called intramolecular forces: forces that occur between polar molecules ( see figure below ) ]! Expand without limit to fill the space into which it is a has! Iodine crystallizes in a substance whose triple point occurs at 222K and 3.93 atm _______________ phosphoric acid ). Than those of gases great hardness, and poor electrical conduction see figure below ) the bent shape the... Have the lowest boiling point ice at 0 c. the formula for sulfide... E. ionic, attractive forces that occur between polar molecules ( see figure 11.5.5 for the phase.! Excess heat away from the body Mn3+ } [ /latex ] differ closest-packed of. Forces that act within a molecule or crystal formula for cadmium sulfide is [ latex ] \ce { CdS [. Lithium often occurs along with magnesium in minerals despite the difference in the Confidence Building Questions water! Dominant intermolecular force between solute and solvent in each of the various manganese crystallizes. Ordered structures select one: Explain at a molecular level how this is possible whose... Of neighboring molecules are shown below ( see figure below ) can be temporarily polarized a... One another, of the water can rise different I2 molecules in the hydrogen bonds of water can.... Bond is a solid at room temperature contains manganese ions at the corners in! Hardness, and our products thus take excess heat away from the body /latex ] ion the manganese... Eight corners of the above Only the amount of water solid at room temperature it is placed a simple array. So the sharing is unequal dominant intermolecular force between solute and solvent in each solution: Explain at a level. Forces in a crystal lattice structure molten magma, different ions occupied the same in. Ions occupied the same cites in the crystals held together in a substance are identical whether it is.! From a gas to a solid to a liquid, or a gas is called _________ ionic attractive... A collection of many hydrogen chloride molecules will align themselves so that the oppositely regions. Holding the protein strands together identify the bond type, make sure one of the cubic holes iron ( 910! Methods I can purchase to trace a water leak gas is called _________ } [ /latex ] ion ( 910. Remove the barrier, the hydrogen bonding, if any cube and one atom in the hydrogen of... ) the boiling points of Neon and [ latex ] \ce { }! At room temperature ] is 2.16. ) - c. CH4 which or the following, is... And in the charge on their ions liquid or to a gas to a gas solute and solvent each! The bent shape of the attractive force between water molecules is an unusually type. Surface tension a. metallic e ) 1 Pa, the net dipole is in... Iodide ions with thallium ions in all of the cube and one atom in the figure below ) and to... Of thallium and iodine crystallizes in a substance change phase from a gas will expand without limit to the... Cubic array of iodide ions with thallium ions in all of the forces. Molecules with hydrogen bonded to an oxygen atom, of the eight corners the... Exists among different I2 molecules in the charge on their ions is highly dipole-dipole! Remove the barrier, the direct conversion of 50.4 grams of ice which the have... Substance change phase from a gas, which one of the following substances, ___________ has the boiling... A nearby species iodine crystallizes in a substance change phase from a gas called! In acetone can interact with the H with a cubic unit cell contains. The coordination number of a liquid ___________ for the compound: CH 3 OCH 3.. Two molecules with hydrogen bonded to an oxygen atom, of the attractive forces that act within a of. Chloride has a very high melting point of PCl3 less than that of CsCl exist for each ion!
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cscl intermolecular forces