The isomerism in organic compounds can be classified broadly into: Isomers can have different physical or chemical properties. Position Isomerism: Position isomerism is the presence of a similar carbon skeleton and functional groups in two or more organic compounds, but the location of the functional groups is different from each other. For example, n-pentane, isopentane, and neopentane are structural isomers. These type of isomers are called solvate isomers. As an example, we consider at least three well established isomers of a complex CrCl 3.6H 2 O these are: give another example of hydrate isomerism and give the percentage wt losses when H2SO4 is passed through [Cr(H2O)6]Cl3- violet, 0% [Cr(H2O)5Cl]Cl2.H2O- light green, 6.75% e.g. (2) Stereo isomerism or space isomerism: Here the isomers differ only in the spatial arrangement of atoms of groups about the central metal atom. Isomerism can be divided into two classes: Constitutional isomerism and Stereoisomerism. C 5 H 10, on the other hand, has three isomers, while C 6 H 14 has nine. These isomers will give different ions in solution. Examples of structural isomers – n-Butane and isobutane. Example is dichlorobis (ethylenediammine) cobalt (III). If the solvent molecule is water, then these isomers are called hydrate isomers. A very similar type of isomerism results from replacement of a coordinated group by a solvent molecule (Solvate Isomerism), which in the case of water is called Hydrate Isomerism. Page | 16 • one isomer [PtBr(NH3)3]NO2 -> NO2- anions in solution another isomer [Pt(NO2)(NH3)3]Br -> Br- anions in solutionc) • C) Hydrate isomerism: the best known example of this occurs for chromium chloride "CrCl3.6H2O" which may contain 4, 5, or 6 coordinated water molecules. For example [Cr (H2O)6]Cl3 is violet colored, [CrCl (H2O)5]Cl2H2O is blue-green, and [CrCl2 (H2O)4]Cl2H2O is dark green. Example : [ Co(NH3)5SO4]Br which on treatment with AgNO3 gives pale yellow precipitate. [ Co(NH3)5Br]SO4 which on treatment with BaCl2 gives a white precipitate BaSO4. The chromium complexes in this example are sometimes said to be an example of hydrate isomerism, a subclass of ionization isomerism in which one or more water molecules exchange with ions. There are several subtypes of structural isomerism: Ionization isomers are coordination compounds that have 2 different ligands swapped between the inner and the outer coordination spheres. In the special case when one of these ligands is a water molecule, the isomerism is called hydrate isomerism. compounds separate out. Isomers are molecules of the same formula but having a different arrangement of their atoms [15]. Metamerism: Metamerism is the presence of same molecular formula with different alkyl groups present on either side of a functional group. H 2 O and [CrCl 2 (H 2 O) 4]Cl 2. • Types of isomerism: a) Structural isomerism i. Linkage isomerism ii. e.g.. An example is provided by the ionisation isomers [Co (NH 3) 5 SO 4 ]Br and [Co (NH 3) 5 Br]SO 4. What is the coordination number of the Fe atom in the following: K … Solvate or hydrate isomerism are the isomers which have the same composition but differ with respect to the number of solvent ligand molecules as well as the counter ion in the crystal lattice. [Cr (H 2 O) 4 Cl 2 ]Cl.2H 2 O – Bright green Tetraaquadichlorochromium (III) chloride dihydrate [Cr (H 2 O) 5 Cl]Cl 2.H 2 O – grey-green Solvate isomers or hydrate isomerism are the isomers which have the same composition but differ with reference to the number of solvent ligand molecules as well as the counter ion in the crystal lattice. 2H 2 O. Linkage isomerism: It arises in a coordination compound containing ambidentate ligand. * Solvent isomerism broadens the definition to allow for the possibility of ammonia or other ligands participating as solvates. [Cr(H 2O) 4Cl 2]Cl.2H 2O bright-green [Cr(H 2O) 5Cl]Cl 2.H 2O grey-green This phenomenon is known as structural isomerism. Optical isomers are two compounds which contain the same number and kinds of atoms, and bonds (i.e., the connectivity between atoms is the same), and different spatial arrangements of the atoms, but which have non-superimposable mirror images.Each non-superimposable mirror image structure is called an enantiomer.Molecules or ions that exist as optical isomers are called chiral. Hydrate isomerism, water molecule can be directly linked to the cation, or it can be found in the outer coordination sphere without being connected to any specific ion. Hydrate Isomerism A well-known and the best example of this isomer is chromium chloride, Cr Cl3.6H2O, which may contain 4, 5, or 6 co-ordinate water molecules. 2. Example: [Co(NH3)5Br]SO4 and [Co(NH3)5SO4]Br (ii)Solvate isomerism: It is isomerism in which solvent is involved as ligand. c) Hydrate isomerism: the best known example of this occurs for chromium chloride "CrCl 3.6H 2O" which may contain 4, 5, or 6 coordinated water molecules. Linkage isomers can exist when one or more ambidentate ligands is bonded to a metal ion. Example: [Co(NH 3) 5(ONO)]Cl the nitrito isomer, connection via O [Co(NH 3) 5(NO 2)]Cl the nitro isomer, connection via N (iv) Hydrate isomerism: Hydrate isomers are the type of isomers which have similar composition but differ in the presence of number of water molecules as ligands. Solvate isomers differ by whether or not a solvent molecule is directly bonded to the metal ion or merely present as free solvent molecules in the crystal lattice. [Cr(H2O)6]Cl3, [Cr(H2O)5.Cl]Cl2.H2O and [Cr(H2O)4.Cl]Cl.2H2O can be given as an example of hydrate isomerism. [Co (H 2 O)5Cl]Cl 2 .H 2 O. The standard example is CrCl 3.6H 2 O which can have three distinctly different crystalline compounds, now known as [Cr(H 2 O) 6]Cl 3 Example 2 [Co(NH3)5Cl]Br vs. [Co(NH3)5Br]Cl. Hydrate isomerism 2. 1 . These are of following types (a) CHAIN ISOMERISM When the isomers have similar molecular formula but differ in nature of carbon chain are called chain isomers and phenomenon is known as chain isomerism. An example is provided by the ionization isomers [Co(NH3)5SO4]Br and [Co(NH3)5Br]SO4. C. ISOMERISM Introduction: The word isomer literally means, “having equal parts”, so compounds are isomers if they have the same number and types of parts-in this case atoms, but different properties.Isomers can be subdivided into two major categories: 1) Stereoisomers (with the same numbers and types of chemical bonds but differing in the spatial arrangement of those bonds), and 2) … Additionally, what is hydrate isomerism explain giving an example? A very similar type of isomerism results from replacement of a coordinated group by a solvent molecule (Solvate Isomerism), which in the case of water is called Hydrate Isomerism. The best known example of this occurs for chromium chloride "CrCl 3.6H 2 O" which may contain 4, 5, or 6 … D and L: The designation of an isomer as D- or L- form is determined by its spatial configuration to … Simple substances which show optical isomerism exist as two isomers known as enantiomers. In the special case when one of these ligands is a water molecule, the isomerism is called hydrate isomerism. In the isomerism, a ligand can form linkage with metal through different atoms. Another example is, [Pt(NH 3) 4 (OH) 2]SO 4 and [Pt(NH 3) 4 SO 4](OH) 2. Linkage isomerism: It arises in a coordination compound containing ambidentate ligand. H2O is blue-green, and [CrCl2(H2O)4]Cl. (iii) Ionisation isomerism This isomerism arise due to exchange of ionisable anion with anionic ligand. For example, the complex with chemical formula CrCl 3.6H 2 O has three hydrate isomers as shown below. When solution which contain two or more salts in simple molecular proportion are evaporated, crystals of new. Examples is [Co(NH 3) 3 (NO 2) 3]. e.g.. (iv) Solvate isomerism This is also known as hydrate isomerism. CHEM1902 Coordination Chemistry Two or more different compounds having the same formula are called isomers. If solvent is water it is called hydrate isomerism, e.g., [Cr(H 2 0)§\ Clz and [CrCl 2 (H 2 O) 4] Cl 2. There are several types of isomers: Constitutional or structural isomers differ in the configuration (bonding) of their atoms. Typically, the water molecules in the outer coordination sphere are shown as water of crystallization. Linkage isomers. Ignoring special cases involving esoteric ligands, then: Geometric Ionisation isomerism iv. Journal of Chemical Education, 49, 3, 204-205, Mar 72 This type of isomerism arises due to the presence of different alkyl chains on each side of the functional group. For example, one of the optical isomers (enantiomers) of the amino acid alanine is known as (+)alanine. different degrees of aggregation) Coordination isomers: found in special cases where both the cation and anion are complexes egs. Another example is, [Pt (NH 3) 4 (OH) 2 ]SO 4 and [Pt (NH 3) 4 SO 4 ] (OH) 2. I think choice D, All of the above may be the correct answer. This property is known as ionization isomerism.. An example of this type of isomerism is furnished by the red-violet, Ionization isomers are the compound salts with similar chemical formula but give dissimilar ions when electrolyzed. (a) [Cr(H 2 O) 6]Cl 3: Violet. Ionization isomerism 4. These primary types are Structural Isomerism and Stereoisomerism. The classification of different types of isomers is illustrated below. Structural isomerism is commonly referred to as constitutional isomerism. The functional groups and the atoms in the molecules of these isomers are linked in different ways. A very similar type of isomerism results from replacement of a coordinated group by a solvent molecule Solvate Isomerism.
(i) Ionisation isomerism (ii) Hydrate isomerism. Hydrate or solvate isomerism: in this they differ in number of molecules of water of crystallization; For example: [Cr(H 2 O) 6]Cl 3 and [Cr(H 2 O) 5 Cl]Cl 2 H 2 Oare hydrate isomers. [Co(NH3)6][Cr(CN)6] vs. [Cr(NH3)6][Co(CN)6] [Pt(NH3)4][PtCl6] vs. [Pt(NH3)4Cl2][PtCl4] Hydration isomers: exchange of water and another ligand between An example is provided by the ionisation isomers [CO(NH 3) 5 SO 4]Br and [CO(NH 3) 5 Br]SO 4. An example of hydrate isomers Examples: [Cr(H2O)6]Cl3 is violet colored, [CrCl(H2O)5]Cl2. (vi) Solvate isomerism : This form of isomerism is known as ‘hydrate isomerism in case where water is involved as a solvent. If solvent is water it is called hydrate isomerism, e.g., [Cr(H2O)6]Cl3 and [CrCl2(H2O)4]Cl2.2H2O (iii)Linkage isomerism: Linkage isomerism arises in a … A solution of one enantiomer rotates the plane of polarisation in a clockwise direction. It is typified by CrCl 3 .6H 2 O which exists in the three distinct forms [Cr(H 2 O) 6 ]Cl 3 (violet), [CrCl(H 2 O) 5 ]Cl 2 .H 2 O (pale green), and [CrCl 2 … In structural isomerism, also called constitutional isomerism, isomers differ from each other in that the constituent atoms are linked in different ways and sequences. This form of isomerism arises when the counter ion in a complex salt is itself a potential ligand and can displace a ligand which can then become the counter ion. n-butane and isobutane have the same molecular formula- C 4 H 10 but different structural formulae. Examples: [Co (H 2 O) 6 ]Cl 3. Polymerization isomers: identical empirical formulae but different molar masses (i.e. Coordination compound - Coordination compound - Isomerism: Coordination compounds often exist as isomers—i.e., as compounds with the same chemical composition but different structural formulas. Hydrate isomerism. isomerism results from replacement of a coordinated group by a solvent molecule (Solvate Isomerism), which in the case of water is called Hydrate Isomerism. (ii) Hydration Isomerism: When there is exchange between the water molecules in coordination sphere and the water of hydration, then the resulting isomers are called hydrate isomers. e.g.. Structural Isomerism - Compounds which show isomerism due to difference in their structures are known as structural isomers. Isomers are especially important in nutrition and medicine because enzymes tend to work on one isomer over another. This enantiomer is known as the (+) form. There is another type of geometrical isomerism which occurs in octahedral coordination entities with [Ma 3 b 3] type formula. Hydrate or solvate isomerism: in this they differ in number of molecules of water of crystallization; For example: [Cr(H 2 O) 6]Cl 3 and [Cr(H 2 O) 5 Cl]Cl 2 H 2 Oare hydrate isomers. This type of isomerism is known as hydrate isomerism and the physical and chemical properties of hydrate isomers are quite different. Hydrate Isomers: Isomers of crystalline complexes that differ in whether water is present inside or outside the coordination sphere. Many different kinds of isomerism occur among coordination compounds. These are examples of structural isomers, or constitutional isomers.Structural isomers have the same molecular formula but a … 2) Hydrate or solvate isomerism: This form of isomerism is known as ‗hydrate isomerism‘ in case where water is involved as a solvent. This is similar to ionisation isomerism. Barbier, J. P.; And Others. Ionisation isomerism arises when an ionisable counter ion (simple ion) itself can act as a ligand. In the case of water, this is called Hydrate isomerism. H 2 O b) [Co(NH 3) 4 Cl 2] NO 2 When dissolved in water [Cr(H 2 O) 6]Cl 3 à[Cr(H 2 O) 6] + 3Cl-(no water molecule ) (ii) Hydrate isomerism: This type of isomerism arises when different number of water molecules are present inside and outside the coordination sphere. Other articles where Ionization isomerism is discussed: coordination compound: Ionization isomerism: Certain isomeric pairs occur that differ only in that two ionic groups exchange positions within (and without) the primary coordination sphere. Ans a) [Cr(H 2 O) 6]Cl 3 &[Cr(H 2 O) 5 Cl] Cl 2. Coordination isomerism 3. Chemqueries "chemqueries.com" will be helpful for students and other academician who are dealing with chemistry and it's usage. Isomers are extremely important in the development of pharmaceuticals, as typically, only one isomer of a particular molecule will exert the desired effect. Isomers are distinct compounds that can have different physical properties such as For example [Cr(H2O)6]Cl3 is violet colored, [CrCl(H2O)5]Cl2H2O is blue-green, and [CrCl2(H2O)4]Cl2H2O is dark green. This includes linkage, coordination, polymerization, hydrate, ligand and ionization isomerism. Pharmaceutical Examples. They yield different numbers of chloride ions in solution as follows. Structural isomerism occurs when the bonds are different. In this isomerism, water is taken as solvent. Known as ‘hydrate isomerism’ when water is involved as a solvent Similar to ionisation isomerism Solvate isomers differ by whether or not a solvent molecule is directly bonded to the metal ion or merely present as free solvent molecules in the crystal lattice. One way to think about this is as follows: Each carbon you add can attach to any of the carbons … (iii) Ionisation isomerism This isomerism arise due to exchange of ionisable anion with anionic ligand. Solvate or hydrate isomerism are the isomers which have the same composition but differ with respect to the number of solvent ligand molecules as well as the counter ion in the crystal lattice. Isomerism is the phenomenon of exhibiting two or more compounds with same molecular formula but different physical and chemical properties.. Isomers are the compounds showing different physical and chemical properties but same molecular formula.. 3. These can be further subdivided as follows: Constitutional isomerism Compounds with the same empirical formulae but differ in atom connectivity. Hydrate isomerism requires water to play two roles, as (1) a ligand and as (2) an additional occupant (or solvate) within the crystal structure. If solvent is water it is called hydrate isomerism, e.g., and . We come across ionization isomerism in coordination compounds. coordinated group by a solvent molecule (Solvate Isomerism). (ii) Coordination isomerism, which arises due to the interchange (between the cationic and the anionic parts of the metal ions) of ligands. It also cites an aldehyde $\ce{CH3CH2(C=O)H}$ and a ketone $\ce{HCH2(C=O)CH3}$. Structural isomers are compound having same molecular formula but different structural formula. As with other compounds, there are several kinds of coordination complex isomers. 1) What type of structural isomerism is shown by [Pt(NH 3) 2 Br 2] and [Pt (NH 3) 4] [Pt Br 4]? In type of isomerism water molecules may occur inside and outside the coordination sphere as a coordinated group or a water of hydration. Hexane, C 6 H 14 , has five possible isomers, while calculations show that there are 75 isomers for decane, C 10 H 22 and up to 366319 isomers for eicosane, C 20 H 42 . This isomerism is best illustrated by the three isomers that have the formula CrCl 3.6H 2 O. Importance of Isomerism . For example, there are three isomers having the molecular formula CrCl3⋅6H2O. Example: Solvate isomerism: It is isomerism in which solvent is involved as ligand. For example [C r(H 2 O)6 ]C l3 Isomerism in Coordination Compounds Lecture 6. This is similar to ionisation isomerism. Hydrate isomerism. For example, the four carbon atoms and ten hydrogen atoms in the butane molecule can be linked in two different ways which will satisfy the valencies of carbon and hydrogen. In this isomerism, water is taken as solvent. Compounds which have same molecular formula but differ in modes of combination or arrangement of atoms within the molecule are known as isomers and this phenomenon is know as isomerism. In organic chemistry, there are many cases of isomerism. All three pairs are structural isomers, with different functional groups, thus functional group isomers (FGIs). All the six water molecules are coordinated to Cr. e.g.. (iv) Solvate isomerism This is also known as hydrate isomerism. Definition of Hydrate Isomers Isomers of crystalline complexes that differ in whether water is present inside or outside the coordination sphere. •Other examples are [Pt(NH3)4Cl2]Br2 and [Pt(NH3)4 Br2]Cl2, [Co(en)2NO2Cl]SCN & [Co(en)2NO2SCN]Cl Hydrate isomerism: This isomerism arises due to different positions of water molecules in the complex (interchange between complex and rest of the compound). As many compounds are prepared in aqueous solutions where water is abundant, complexes can precipitate or crystallize by water of crystallisation outside the coordination sphere or through coordinated water (ligand) inside the coordination sphere. When dissolved in water [Cr(H 2 O) 6]Cl 3 à[Cr(H 2 O) 6] + 3Cl- (no water molecule ) 4- Hydrate isomerism This type of isomerism is similar to ionization isomerism. 2. The exchange of such counter ions with one or more ligands in the coordinatioin entity will result in ionisation isomers. Stereoisomers: Similar to organic compounds, coordination compounds also exhibit stereoisomerism. [CrCl 2 (H 2 O) 4 ]Cl.H 2 O bright green CrCl (H 2 O) 5 ]Cl2.H 2 O grey-green Optical Isomers. This type of isomerism is known as hydrate isomerism and the physical and chemical properties of hydrate isomers are quite different. As an example, we consider at least three well established isomers of a complex CrCl 3 .6H 2 O these are: There is no "number of chain isomers formula" for alkanes, and the number quickly grows cumbersome (for example, decane, or C 10 H 22, has a whopping 75 isomers). For example, the formula C 4 H 10 represents both butane and 2‐methylpropane. Structural Isomers There are several types of this isomerism frequently encountered in coordination chemistry and the following represents some of them. Stereoisomers occur when the ligands have the same bonds, but the bonds are in different orientations relative to one another. A subdivision of this type of isomerism, known as “hydrate isomerism”, occurs when water may be inside or outside the coordination sphere. The following are some of the more common types. (d) Hydrate Isomerism: This isomerism arises when different number of water molecules are present within and outside the co-ordination sphere. structural isomerism in coordination compounds, example of isomerism, define isomerism. Answer: 1. Hydrate isomers are obtained when H 2 O molecules acting as ligands are replaced by the anions present outside the coordination sphere. This is similar to ionisation isomerism. The Hydration Isomers of Chromium(III) Chloride. Keggin structure is the best known structural form for heteropoly acids.It is the structural form of α-Keggin anions, which have a general formula of [XM 12 O 40] n−, where X is the heteroatom (most commonly are P 5+, Si 4+, or B 3+), M is the addenda atom (most common are molybdenum and tungsten), and O represents oxygen. In the case of water, this is called Hydrate isomerism. The best-known examples of Hydrate Isomerism or Solvate Isomerism type of isomerism occurs for chromium chloride “CrCl 3.6H 2 O” which may contain 4, 5, (or) 6 coordinated water molecules. Linkage isomers are coordination compounds that have the same composition but differ in the connectivity of the ligand to the metal. An example is provided by the ionisation isomers [Co(NH 3) 5 SO 4]Br and [Co(NH 3) 5 Br]SO 4. Linkage isomerism 5. Isomerism Definition. Compounds which have same molecular formula but differ in modes of combination or arrangement of atoms within the molecule are known as isomers and this phenomenon is know as isomerism. Isomers can have different physical or chemical properties. As for example, the cis and trans isomers of but-2-ene are as follows: The hydrocarbons ethane, ethene, and ethyne provide an example of how each type of bond can affect the geometry of a molecule: Ethane: tetrahedral organization of bond substituents about the carbon atoms. Explain ionisation isomerism with suitable example. Give example of following types of isomerism: 1. Free library of english study presentation. It has different number of water molecules in the coordination sphere and outside it. An example of functional isomerism can be observed in the compound C 3 H 6 O. Metamerism. Generally the number of isomers increases. Example: Solvate isomerism: It is isomerism in which solvent is involved as ligand. (iii) Ionization Isomerism, which arises when counter ions can act as potential ligands in complex salts. (iv) Solvate isomerism, which arises when water is used as a solvent. Enjoy the videos and music you love, upload original content, and share it all with friends, family, and the world on YouTube. This brief overview uses a carboxylic acid and ester pair as an example of FGI, which validates choice B. This form of isomerism arises when the counter ion in a complex salt is itself a potential ligand and can displace a ligand which can then become the counter ion. The best known example of this occurs for chromium chloride (\(\ce{CrCl_3 \cdot 6H_2O}\)) which may contain 4, 5, or 6 coordinated water molecules (assuming a coordination number of 6). CrCl3 6H2O that is found in 3-isomeric forms. It is of two types : It is of two types : (i) Geometrical or Cis-trans isomerism : This isomerism arises due to the difference in geometrical arrangement of the ligands around the central atom. These are the only two isomers of this molecule. Explain the following types of isomerism in co-ordination compounds. INTRODUCTION. Optical isomerism 6. cis-trans isomerism 7. fac-mer isomerism 50. The best known examples of this type of isomerism occurs for chromium chloride "CrCl 3.6H 2 O" which may contain 4, 5, (or) 6 coordinated water . As for example, the Example 1. For example, a thiocyanato group could be connected to the metal atom by either the S atom or the N atom. An example of this type of isomerism is furnished by the red-violet, [Co(NH 3) 5 Br] ... Hydrate isomerism or Solvate isomerism . This form of isomerism is known as ‘hydrate isomerism’ in case where water is involved as a solvent. The substituted xanthines are a good example of an isomer found in food and drugs. You can demonstrate this to yourself by drawing all possible structures for propane (1), butanes (2), pentanes (3), and hexanes (5). isomers, ions, ligands, types of structural isomerism, structural isomerism pdf. This type of isomerism is also observed when bidentate ligands L–L [e.g.,NH 2 CH 2 CH 2 NH 2 (en)] are present in complexes with [MX 2 (L–L) 2] type formula. Consider precipitation [Co(NH3)5Cl]Br(aq) + AgNO3(aq) [Co(NH3)5Cl]NO3(aq) + AgBr(s) [Co(NH3)5Br]Cl(aq) + AgNO3(aq) [Co(NH3)5Br]NO3(aq) + AgCl(aq) Hydrate isomers have the same composition but differ In the number of water molecules present as ligands And the phenomenon is called hydrate isomerism. It has different number of water molecules in the coordination sphere and outside it. Solvate 2H 2 O are examples of hydrate or solvate isomers. Example: C 4 H 10 For example, only one isomer for ibuprofen will bind to the necessary target in the human body and induce pain relief. Coordination compounds having the same molecular formula but forming different ions in solution are called ionization isomers. Search the Dictionary for More Terms Ans a) Ligand isomerism b) Coordination isomerism c) Linkage isomerism d) Coordination position isomerism 2) Out of the following which is hydrate isomerism example? For example: [CoCl2(NH3)4]+, [Co(NH3)5Br]2+ • Isomers: Two or more compounds which have same chemical formula but different arrangement of atoms are called isomers. A very similar type of isomerism results from replacement of a coordinated group by a solvent molecule (Solvate Isomerism). Hydrocarbons may contain various combinations of single, double, and triple carbon-carbon bonds. [Co (H 2 O)4Cl 2 ]Cl.2H 2 O. Share and download educational presentations online. Hydrate isomerism or solvate isomers are a special case of ionisation isomerism in which compounds differ depending on the number of the solvent molecule directly bonded to the metal ion. Solvate isomerism or hydrate isomerism iii. Example: and . Theobromine, caffeine, and theophylline are isomers, differing in the placement of methyl groups. In the case of water, this is called Hydrate isomerism.
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