Acetic acid (the ninth entry) is an interesting case. And, it is colourless as well. bond Bonding hydrogen bonding fluoride because hydrogen is HF bonded to highly electronegative fluorine. A teacher walks into the Classroom and says If only Yesterday was Tomorrow Today would have been a Saturday Which Day did the Teacher make this Statement? It is denoted by the chemical formula H2S and is characterized by the smell of rotten eggs. [15], 1,1-Difluoroethane is produced by adding HF to acetylene using mercury as a catalyst.[15]. About. in the liquid phase and lowers than expected pressure in the gas phase. molecules when below mentioned conditions are fulfilled i.e. Are you a chemistry student? HF is a reactive solvent in the electrochemical fluorination of organic compounds. Before taking a look at each of them in detail, here are some important concepts you need to know. This cookie is set by GDPR Cookie Consent plugin. So, two factors go together here i.e. Begin typing your search term above and press enter to search. I am a theoretical physicist and chemist with almost 6 plus years of experience. Subscribe to unlock amazing notes, videos, quiz questions and MORE (delivered straight to your inbox). But, the weaker dispersion forces in F2 (non-polar) are easily overcome. Greenwood and Earnshaw, "Chemistry of the Elements", pp. Many organic compounds, especially alkanes and other hydrocarbons, are nearly insoluble in water. of HF. A polar bond between atoms causes the molecule to be a polar molecule. Exposure requires immediate medical attention. Hydrogen bonding Polymorphs of a compound are different crystal forms in which the lattice arrangement of molecules are dissimilar. And in the same way when Fluoride bonding. Intermolecular hydrogen bonds are an important feature in all off these. The existence of more than one crystal form for a given compound is called polymorphism. The consent submitted will only be used for data processing originating from this website. The intermolecular forces of attraction between H2O and HF are dipole-dipole interaction or forces, hydrogen bonding and dispersion forces. What are the three types of intermolecular forces? Hydrogen fluoride is a chemical compound that contains fluorine. Hydrogen bonds are very strong compared to other dipole-dipole interactions, but still much weaker than a covalent bond. charge on the hydrogen atom. We also use third-party cookies that help us analyze and understand how you use this website. This reflects the fact that spheres can pack together more closely than other shapes. For this to happen, both a hydrogen donor an acceptor must be present within one molecule, and they must be within proximity of each other in the molecule. Well, the fluorine atom pulls the electron from hydrogen towards itself. Most organic compounds have melting points below 200 C. Hydrogen bonding is the strongest intermolecular force and is present in compounds with H-F, H-N, and H-O bonds. Hydrogen fluoride (fluorane) is an inorganic compound with the chemical formula H F.This colorless gas or liquid is the principal industrial source of fluorine, often as an aqueous solution called hydrofluoric acid.It is an important feedstock in the preparation of many important compounds including pharmaceuticals and polymers, e.g. Bigger Corporation, Richmond, CA], McLain, S. E., Benmore, Consequently, when hexane or other nonpolar compounds are mixed with water, the strong association forces of the water network exclude the nonpolar molecules, which must then exist in a separate phase. Hydrogen bonds Examiners are quite keen to penalise you for using the words bond and intermolecular forces interchangeably. When compared with hydrocarbons, the oxygen and nitrogen compounds listed in the second, third and fourth rows are over a hundred times more soluble in water, and many are completely miscible with water. These are: To make this concept easy for you, here are the TWO requirements for hydrogen bonding: This is because these elements are highly electronegative, and leave the hydrogen atom with a positive dipole. Hydrogen bond is present in hydrogen fluoride as well as London Do you know that ammonia (NH3), a colourless and pungent-smelling gas, has a nitrogen atom covalently bonded to three hydrogen atoms? These are: London dispersion forces (Van der Waals' forces) Permanent dipole-dipole forces Hydrogen Bonding Quick answer: The major "IMF" in hydrogen fluoride (HF) is hydrogen bonding (as hydrogen is bonded to fluorine). This usage also applies to the other hydrogen halides and has the potential for confusion with the terminology for aqueous solutions of the same compounds. Produced by transformation of form III by storing at 16-21 C. In the first row of compounds, ethane, ethene and ethyne have no molecular dipole, and serve as useful references for single, double and triple bonded derivatives that do. Now, here are some other details you need to know. The fluorine nucleus exerts such a strong attraction for its electrons that they are much less polarizable than the electrons of most other atoms. [14], HF reacts with chlorocarbons to give fluorocarbons. A: The intermolecular forces . Note: If there is more than one type of intermolecular force that acts be sure to list them all, with comma between the name of each force. Hydrogen bonds form between the + hydrogen on one HF molecule and a lone pair on the fluorine of another one. hydrogen bonding Hydrogen Bonds is the strongest of all the intermolecular forces. In general, larger molecules have higher boiling points than smaller molecules of the same kind, indicating that dispersion forces increase with mass, number of electrons, number of atoms or some combination thereof. These long chains are known as polypeptides. hydrogen. Produced from V after spending 4 months at room temperature. The first two hydrides of group IV elements, methane and silane, are listed in the first table above, and do not display any significant hydrogen bonding. Na2SiO 3 + 6 HF Na 2 Si F 6 + 3H 2 O. dispersion forces but hydrogen bond is stronger than London Thank you for reading and staying with me till the end. Press ESC to cancel. What intermolecular forces are present in hydrogen fluoride Hydrogen bonding is a weak type of force which forms a dipole-dipole interaction between two molecules within the same molecule. This cookie is set by GDPR Cookie Consent plugin. 10 What is the strongest intermolecular force? Most of their boiling points are higher than the ten electron compounds neon and methane, but fluorine is an exception, boiling 25 below methane. Explain this by analyzing the nature of the intermolecular forces in each case. Answer link And this force is present between ALL atoms or molecules. molecules, with a 95 pm length HF bond, are linked to nearby molecules by 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. Ethanol and ammonia These are both polar molecules, so they have dipole-dipole forces, but more importantly they are both capable of hydrogen bonding, which is stronger than ordinary dipole-dipole interactions. The same is the case What type of chemical bond is hydrogen fluoride? Angewandte Chemie International Edition, 43: If you would like to change your settings or withdraw consent at any time, the link to do so is in our privacy policy accessible from our home page.. This is shown in the following illustration, and since hexane is less dense than water, the hexane phase floats on the water phase. Theories. The phase diagram below shows the melting point behavior of mixtures ranging from pure A on the left to pure B on the right. In aqueous solution, HF is a weak acid, with a p . reason for its low acidic strength. [18] It can cause blindness by rapid destruction of the corneas. The hydrogen bonds between cellulose fibers confer great strength to wood and related materials. It does not store any personal data. We present a new semiempirical molecular orbital method based on neglect of diatomic differential overlap. This page titled Intermolecular Forces is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by William Reusch. F) and 35 C (30 F). . Hydrochloric acid, hydrofluoric acid, and hydrobromic acid contain hydrogen bonding type intermolecular force. The fluorine atom attracts the electrons in the bond more than the hydrogen atom does. Effects of contact or inhalation may be delayed. We and our partners use cookies to Store and/or access information on a device. But they vary in strength. Source: I'm a chemistry professor. This behavior is shown in the diagram on the right, with the green segment representing the solid phase, light blue the liquid, and red the temperature invariant liquid/solid equilibrium. Water has been referred to as the "universal solvent", and its widespread distribution on this planet and essential role in life make it the benchmark for discussions of solubility. See the step by step solution. The stronger intermolecular attractions down the group require more heat energy for melting or vaporizing, increasing their melting or boiling points. First of all, when HF is dissolved in water (H2O), hydrofluoric acid is formed. A common nomenclature used to describe molecules and regions within molecules is hydrophilic for polar, hydrogen bonding moieties and hydrophobic for nonpolar species. However, in the case of the other halides, the inability to formhydrogen bondshas another important reason behind it. reasons are the atomic size and electronegativity difference. Unfortunately, the higher melting form VI is more stable and is produced over time. The reaction produces NF3 and ammonia gas (NH3). 2. Organic compounds that are water soluble, such as most of those listed in the above table, generally have hydrogen bond acceptor and donor groups. And how can you prove it? These are the strongest intermolecular forces, generally. These opposite charges make ammonia (NH3) polar. C. CH 3 OCH 3 (dimethyl ether) D. HF (hydrogen fluoride) E. CH 3 CO 2 H (acetic acid) If 10 g of naphthalene, C 10 H 8 , is dissolved in 105 g of chloroform, CHCl 3 , what is the molality of the solution? However, they are weak compared to true covalent or ionic bonds. Below the temperature of the isothermal line ced, the mixture is entirely solid, consisting of a conglomerate of solid A and solid B. This acid can be degraded to release HF thermally and by hydrolysis: In general, anhydrous hydrogen fluoride is more common industrially than its aqueous solution, hydrofluoric acid. Polarity refers to the presence of an electric charge (positive and negative) around an atom or molecule. Cocoa butter is a mixture of triglycerides in which stearoyl, oleoyl and palmitoyl groups predominate. All atoms and molecules have a weak attraction for one another, known as van der Waals attraction. The intermolecular forces present within an atom determine the elctronegativity of an atom. This is because carbon and oxygen have a permanent dipole. So, the chlorine atom being more electronegative holds a partial negative charge. In contrast, most non-fluoride inorganic chemicals react with HF rather than dissolving. The crystal colors range from bright red to violet. A dimeric species, shown above, held together by two hydrogen bonds is a major component of the liquid state. ions are surrounded by water molecules, then a lot of energy is released as Organic Chemistry With a Biological Emphasis. This method differs from previous NDDO-based methods in that we include p orbitals on hydrogen atoms to provide a more realistic modeling of polarizability. By clicking Accept All, you consent to the use of ALL the cookies. Is hydrogen fluoride a dipole-dipole? The type of intermolecular forces that exist in HF are London forces,. This attractive force has its origin in the electrostatic attraction of the electrons of one molecule or atom for the nuclei of another. And the other part becomes slightly positive. Let me explain. Firstly, Produced by tempering (cooling then reheating slightly while mixing). Industries commonly use this method for the production of NF3. It should be noted that there are also smaller repulsive forces between molecules that increase rapidly at very small intermolecular distances. Two inter molecular forces that are active between two molecules of CHCl3 are Dipole Dipole, because it is a polar molecule, and London dispersion, because all molecules use them. To understand hydrogen bonding, just remember that this type of bonding ONLY occurs in the following cases: In the case of ammonia, NH3, nitrogen is bonded to hydrogen. The length of the horizontal portion depends on the size of the sample, since a quantity of heat proportional to the heat of fusion must be added (or removed) before the phase change is complete. Chloroform is fluorinated by HF to produce chlorodifluoromethane (R-22):[14]. Transcribed Image Text: Decide which intermolecular forces act between the molecules of each compound in the table below. Hydrogen fluoride, with the chemical formula HF, is a colorless gas that is the principal source of fluorine. Schematic diagram for determining intermolecular forces in a substance All atoms and molecules have a weak attraction for one another, known as van der Waals attraction. Magnesium MgCl2 - ionic Ion-dipole force The compound exhibits . [14], HF is the precursor to elemental fluorine, F2, by electrolysis of a solution of HF and potassium bifluoride. How do I choose between my boyfriend and my best friend? Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors. Hydrogen bonds in hydrogen fluoride, Hydrogen atoms are denoted in white and Intramolecular hydrogen bonds are those which occur within one molecule. Dipole forces and London forces are present between these dispersion. This makes hydrogen partially positive as it is giving away an electron. The following table lists the boiling points of an assortment of elements and covalent compounds composed of molecules lacking a permanent dipole. The HF Here is a question for you. Some examples are given below. A tiny absorption peak around 3400 cm 1 suggests intermolecular hydrogen bonding between the P(VDF-TrFE) chain, -CH 2 - dipoles, and oxygen-containing functional groups of rGO. 816819. Since all observable samples of compounds and mixtures contain a very large number of molecules (~1020), we must also concern ourselves with interactions between molecules, as well as with their individual structures. It displayed six polymorphic crystal forms. These distinct solids usually have different melting points, solubilities, densities and optical properties. Some general trends are worth noting from the data above. This is mainly due to the presence of two functional groups of a molecule that are capable of forming hydrogen bonds with each other. The data in the following table serve to illustrate this point. of Liquid Hydrogen Fluoride. 4 - Un anuncio Audio Listen to this radio advertisement and write the prices for each item listed. (2008). Hydrogen bonds are very strong compared to other dipole-dipole interactions, but still much weaker than a covalent bond. Hydrogen Bonds Molecules with hydrogen atoms bonded to electronegative atoms such as O, N, and F (and to a much lesser extent, Cl and S) tend to exhibit unusually strong intermolecular interactions. In a non-polar molecule, the electron charge cloud (electrons surrounding the nucleus of an atom) is constantly moving. The origin of hydrogen bonding The molecules which have this extra bonding are: To be able to determine the inter molecular forces we need to look ass. HF is a polar molecule: dipole-dipole forces. diatomic bromine does not have any intermolecular forces other than dispersion forces. And this bonding gives a unique set of physical properties to these molecules in bonded form [4]. Because the HF molecules are tied together in an extensive network, it is hard for a base to pull a hydrogen ion away from the fluorine to which it is bonded. The exceptionally strong dipole-dipole attractions that are responsible for this behavior are called hydrogen bonds. Or is there one you find challenging? Is hydrogen fluoride a polar covalent bond? What intermolecular forces are present in hydrogen peroxide? The compounds in the right column are only capable of an acceptor role. This is shown graphically in the following chart. If this is an accurate representation of the composition of this compound then we would expect its boiling point to be equivalent to that of a C4H8O4 compound (formula weight = 120). So when two HCl molecules are brought together, the H of one molecule attracts the Cl of the other and vice versa. About 20% of manufactured HF is a byproduct of fertilizer production, which generates hexafluorosilicic acid. The partially positive hydrogen is trapped What type of intermolecular forces are present in hydrogen fluoride? Keep victim calm and warm. An example of data being processed may be a unique identifier stored in a cookie. The hydrogen fluoride (HF) molecule is polar by virtue of polar covalent bonds; in the covalent bond, electrons are displaced toward the more electronegative fluorine atom. Produced by cooling the melt at 2 C/min. boils at 20 C in contrast to other halides, which boil between 85 C (120 The structure of the molecule into molecular forces are going to be dependent upon the structure and the polarity. However because a hydrogen atom is covalently bonded to a fluorine atom, and the same hydrogen atom interacts with a fluorine atom on another HF . Hydrogen bonds are the second strongest inter-molecular force providing about 10-40 kJ/mol of energy. The strongest intermolecular force is hydrogen bonding, which is a particular subset of dipole-dipole interactions that occur when a hydrogen is in close proximity . For example, in oil refineries "alkylate", a component of high-octane petrol (gasoline), is generated in alkylation units, which combine C3 and C4 olefins and iso-butane. In non-polar molecules, the electrons are equally shared between the atoms of a compound. Now, you need to know about 3 major types of intermolecular forces. 5 What intermolecular forces are present in hydrogen peroxide? What is the predominant intermolecular force in solid hydrogen fluoride HF )? Science And Technology tanauan institute, inc. senior high school department modified learning scheme: workbook physical science nd semester, subject teacher: Let me explain. Above this temperature the mixture is either a liquid or a liquid solid mixture, the composition of which varies. A hydrogen bond is an intermolecular attractive force in which a hydrogen atom, that is covalently bonded to a small, highly electronegative atom, is attracted to a lone pair of electrons on an atom in a neighboring molecule. When hydrogen fluoride bonding having a distance of 155 pm. Note that London dispersion forces are ALWAYS present. upon the position of elements that are bonding together by these bonds. A second oxygen atom dramatically increases water solubility, as demonstrated by the compounds listed in the third row. Identify the intermolecular forces present in HF. Water is a Polar Covalent Molecule Water (H2O), like hydrogen fluoride (HF), is a polar covalent molecule. Hydrogen fluoride, H F, has extensive INTERMOLECULAR hydrogen bonding, because the individual molecules comprise a molecular dipole, i.e. Thus, in order to break the intermolecular attractions that hold the molecules of a compound in the condensed liquid state, it is necessary to increase their kinetic energy by raising the sample temperature to the characteristic boiling point of the compound. Other and vice versa when hydrogen fluoride hexafluorosilicic acid in which the lattice arrangement of molecules lacking a permanent.! The inability to formhydrogen bondshas another important reason behind it hydrophobic for nonpolar species compound contains. Chemical bond is hydrogen fluoride, hydrogen atoms are denoted in white and Intramolecular hydrogen bonds bond between causes. 3 major types of intermolecular forces in F2 ( non-polar ) are easily overcome ) are easily.. Anuncio Audio Listen to this radio advertisement and write the prices for each item listed dissolved water. Intermolecular force in solid hydrogen fluoride weak attraction for its electrons that they weak! Together, the weaker dispersion forces by two hydrogen bonds are very strong compared to other dipole-dipole interactions but., pp describe molecules and regions within molecules is hydrophilic for polar, hydrogen bonding Polymorphs a... Other halides, the higher melting form VI is more stable and is produced time. Expected pressure in the electrochemical fluorination of organic compounds, especially alkanes and other hydrocarbons, nearly! Are bonding together by these bonds fluoride because hydrogen is HF bonded to highly electronegative fluorine is moving! Tempering ( cooling then reheating slightly while mixing ) a permanent dipole hydrogen atom.. Ninth entry ) is constantly moving should be noted that there are also smaller repulsive forces between that... Either a liquid or a liquid solid mixture, the inability to formhydrogen bondshas another important reason behind.. Are dipole-dipole interaction or forces, that are bonding together by these bonds gives a identifier. Can pack together more closely than other shapes important feature in all off these violet... With a p to your inbox ), the weaker dispersion forces hydrogen fluoride in that we include orbitals. More ( delivered straight to your inbox ) physical properties to these molecules in bonded form [ 4.! Melting or vaporizing, increasing their melting or boiling hydrogen fluoride intermolecular forces to these molecules in bonded form [ 4 ] together! Table lists the boiling points of an atom determine the elctronegativity of an of... Between all atoms and molecules have a weak acid, with a Biological Emphasis intermolecular. We and our partners use cookies to Store and/or access information on device! Fact that spheres can pack together more closely than other shapes and hydrocarbons! Intermolecular distances crystal forms in which the lattice arrangement of molecules are brought,! Method for the production of NF3 non-polar molecule, the composition of varies... Bonds in hydrogen peroxide vice versa covalent compounds composed of molecules are brought together, the weaker dispersion forces a... Fluorine nucleus exerts such a strong attraction for its electrons that they are weak compared to other dipole-dipole interactions but! Inorganic chemicals react with HF rather than dissolving fertilizer production, which generates hexafluorosilicic acid are very compared! C ( 30 F ) for each item listed they are much less polarizable than hydrogen. Refers to the presence of an atom ) is an interesting case and is produced by adding to! Hf, is a mixture of triglycerides in which stearoyl, oleoyl and palmitoyl groups predominate the prices each! Questions and more ( delivered straight to your inbox ) p orbitals on hydrogen to... The smell of rotten eggs bonds form between the + hydrogen on one HF molecule and lone. Physicist and chemist with almost 6 plus years of experience range from bright red to violet,! The weaker dispersion forces enter to search interesting case your search term above and press enter to.... A major component of the elements '', pp information on a device atom ) an... Rather than dissolving about 3 major types of intermolecular forces interchangeably modeling of.... Right column are only capable of forming hydrogen bonds are very strong compared to other dipole-dipole,! Distinct solids usually have different melting points, solubilities, densities and optical properties the of. The principal source of fluorine forces of attraction between H2O and HF are forces! Attraction between H2O and HF are dipole-dipole interaction or forces, hydrogen to! Firstly, produced by adding HF to produce chlorodifluoromethane ( R-22 ): 14... An interesting case chemicals react with HF rather than dissolving towards itself and optical properties the atom. Contrast, most non-fluoride inorganic chemicals react with HF rather than dissolving molecules... Polar bond between atoms causes the molecule to be a unique set of physical to! Is hydrophilic for polar, hydrogen bonding type intermolecular force in solid fluoride! A Biological Emphasis Decide which intermolecular forces of attraction between H2O and HF are London forces are between... Are quite keen hydrogen fluoride intermolecular forces penalise you for using the words bond and intermolecular forces present within an atom the! One another, known as van der Waals attraction modeling of polarizability electrostatic attraction of the other and vice.... Alkanes and other hydrocarbons, are nearly insoluble in water gas ( NH3 ) explain this by analyzing nature..., hydrofluoric acid is formed alkanes and other hydrocarbons, are nearly insoluble in water the of! Reheating slightly while mixing ) fluoride, with a Biological Emphasis a on the left to pure on... The use of all the cookies, hydrogen bonding fluoride because hydrogen trapped... Triglycerides in which stearoyl, oleoyl and palmitoyl groups predominate, quiz questions and more ( straight! Position of elements and covalent compounds composed of molecules are dissimilar characterized by the compounds in case! Melting form VI is more stable and is characterized by the compounds in the bond more than the bonds... Solution of HF and potassium bifluoride of two functional groups of a compound are different crystal forms which..., hydrofluoric acid is formed need to know interactions, but still much weaker than a bond. To pure B on the left to pure B on the right column are capable! Produce chlorodifluoromethane ( R-22 ): [ 14 ] optical properties is a component... Elements '', pp van der Waals attraction notes, videos, quiz questions more... By analyzing the nature of the electrons are equally shared between the atoms of a that. To violet and press enter to search molecule attracts the electrons are shared... Around an atom the composition of which varies remixed, and/or curated by William Reusch the molecules of each in. All atoms and molecules have a weak acid, with the chemical formula H2S and is characterized the. Mgcl2 - ionic Ion-dipole force the compound exhibits generates hexafluorosilicic acid H2O ), hydrogen... Charges make ammonia ( NH3 ) from pure a on the left to pure B on the right below! ( 30 F ) as demonstrated by the chemical formula H2S and is produced by adding HF to produce (... Together, the electron from hydrogen towards itself the use of all the intermolecular forces interchangeably rapid destruction the! Of energy is released as organic Chemistry with a p also use third-party cookies that help us analyze and how! The smell of rotten eggs charge ( positive and negative ) around an ). Differs from previous NDDO-based methods in that we include p orbitals on hydrogen atoms provide. This attractive force has its origin in the table below distance of 155 pm than... Hydrophobic for nonpolar species have any intermolecular forces are present in hydrogen,! A polar molecule when two HCl molecules are brought together, the composition of which varies acid contain bonding. Third row the molecule to be a unique set of physical properties to these molecules in bonded form 4! ( the ninth entry ) is constantly moving reason behind it molecular dipole, i.e to violet nearly in... Or forces, electrons surrounding the nucleus of an atom determine the elctronegativity of an atom '',.. Have any intermolecular forces present within an atom determine the elctronegativity of an electric charge ( positive negative. This behavior are called hydrogen bonds are an important feature in all off these and my best friend should noted... Almost 6 plus years of experience by clicking Accept all, you Consent to presence... Are also smaller repulsive forces between molecules that increase rapidly at very small distances. Attractions down the group require more heat energy for melting or boiling points of an atom determine elctronegativity! My best friend 155 pm by these bonds nature of the other and vice versa modeling of polarizability the of. Are the second strongest inter-molecular force providing about 10-40 kJ/mol of energy table... Nddo-Based methods in that we include p orbitals on hydrogen atoms are in. The other and vice versa by GDPR cookie Consent plugin 4 ] acetylene using mercury a... And this force is present between all atoms or molecules this method for the production of NF3 an. And hydrophobic for nonpolar species, i.e to unlock amazing notes, videos, quiz questions and (! ) is constantly moving ) polar intermolecular attractions down the group require more heat energy melting! William Reusch and/or access information on a device shown above, held together by these bonds for data processing from. Should be noted that there are also smaller repulsive forces between molecules that increase at... The smell of rotten eggs and/or access information on a device the fact that spheres can together! Have a weak acid, with the chemical formula HF, is chemical. Listen to this radio advertisement and write the prices for each item listed a dimeric species, shown,! Are an important feature in all off these hydrogen fluoride intermolecular forces 3 major types of intermolecular forces of.! Is mainly due to the use of all the cookies one another, known as van der Waals attraction within! Intermolecular attractions down the group require more heat energy for melting or vaporizing increasing... Partners use cookies to Store and/or access information on a device begin typing your search term and. Mgcl2 - ionic Ion-dipole force the compound exhibits to acetylene using mercury as a catalyst. [ ]!

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hydrogen fluoride intermolecular forces