Making a saline water solution by dissolving table salt (NaCl) in water

In chemistry, a solution is a homogeneous mixture composed of two or more substances. Saline water is a general term for Water that contains a significant concentration of dissolved Salts ( NaCl) Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants For sodium chloride in the diet see Salt. Sodium chloride, also known as common salt, table salt, or Halite, is a Water is a common Chemical substance that is essential for the survival of all known forms of Life. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties In Chemistry, a mixture is a substance made by combining two or more different materials without a chemical reaction occurring (the objects do not bond together In such a mixture, a solute is dissolved in another substance, known as a solvent. A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. A common example is a solid, such as salt or sugar, dissolved in water, a liquid. A solid' object is in the States of matter characterized by resistance to Deformation and changes of Volume. Salt is a Dietary mineral composed primarily of Sodium chloride that is essential for Animal life but toxic to most land plants Sugar is a class of edible Crystalline substances mainly Sucrose, Lactose, and Fructose. Water is a common Chemical substance that is essential for the survival of all known forms of Life. Liquid is one of the principal States of matter. A liquid is a Fluid that has the particles loose and can freely form a distinct surface at the boundaries of Gases may dissolve in liquids, for example, carbon dioxide or oxygen in water. This page is about the physical properties of gas as a state of matter Solvation, commonly called dissolution, is the process of attraction and association of Molecules of a Solvent with molecules or Ions of a Carbon dioxide ( Chemical formula:) is a Chemical compound composed of two Oxygen Atoms covalently bonded to a single Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the Liquids may dissolve in other liquids. Gases can combine with other gases to form mixtures, rather than solutions. ^[1] All solutions are characterized by interactions between the solvent phase and solute molecules or ions that result in a net decrease in free energy. Under such a definition, gases typically cannot function as solvents, since in the gas phase interactions between molecules are minimal due to the large distances between the molecules. This lack of interaction is the reason gases can expand freely and the presence of these interactions is the reason liquids do not expand.

Examples of solid solutions are alloys, certain minerals and polymers containing plasticizers. An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has A mineral is a naturally occurring substance formed through geological processes that has a characteristic chemical composition a highly ordered atomic structure and specific Plasticizers are additives that increase the Plasticity or Fluidity of the material to which they are added these include plastics cement concrete wallboard and The ability of one compound to dissolve in another compound is called solubility. Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. The physical properties of compounds such as melting point and boiling point change when other compounds are added. The melting point of a solid is the temperature range at which it changes state from solid to Liquid. The boiling point of a liquid is the temperature at which the Vapor pressure of the liquid equals the environmental pressure surrounding the liquid Together they are called colligative properties. Colligative properties are properties of solutions that depend on the number of particles in a given volume of solvent and not on the mass of the particles There are several ways to quantify the amount of one compound dissolved in the other compounds collectively called concentration. In Chemistry, concentration is the measure of how much of a given substance there is mixed with another substance Examples include molarity, molality, and parts per million (ppm).

Solutions should be distinguished from non-homogeneous mixtures such as colloids and suspensions. A colloid is a type of mechanical Mixture where one substance is dispersed evenly throughout another In Chemistry, A suspension is a Heterogenous fluid containing Solid particles that are sufficiently large for Sedimentation.

Types of solutions

Many types of solutions exist, as solids, liquids and gases can be both solvent and solute, in any combination:

Solvents

Main article: Solvent

Liquid solvents can be broadly classified into polar and non-polar solvents. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 Duralumin (also called duraluminum, duraluminium or dural) is the trade name of one of the earliest types of age-hardenable Aluminium alloys The M acro E xpansion T emplate A ttribute L anguage complements TAL, providing macros which allow the reuse of code across An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has A solvent is a liquid or gas that dissolves a solid liquid or gaseous Solute, resulting in a Solution. "Polar molecule" and "Non-polar" redirect here A common measure of the polarity of a solvent is the dielectric constant. Measurement The relative static permittivity εr can be measured for static Electric fields as follows first the Capacitance of a test The most widely used polar solvent is water, with a dielectric constant of 78. 5. Ethanol, with a dielectric constant of 24. 3, has intermediate polarity. An example of a non-polar solvent is hexane, which has a dielectric constant of 1. Hexane is an Alkane Hydrocarbon with the Chemical formula CH3(CH24CH3 or C6H14 9. Generally polar or ionic compounds will only dissolve in polar solvents. A simple test for the polarity of a liquid solvent is to rub a plastic rod, to induce static electricity. Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products For the science of static charges see Electrostatics Static electricity refers to the accumulation of excess Electric charge in a Then hold this charged rod close to a running stream of the solvent. If the path of the solvent deviates when the rod is held close to it, it is a polar solvent. Certain molecules have polar and non-polar regions, for example sodium dodecyl sulfate. Sodium lauryl sulfate ( SLS) or sodium dodecyl sulfate ( SDS or NaDS ( C 12 H 25 S[[oxygen O]]4 This class of molecules (called amphipathic molecules) includes surfactants like soaps and emulsifiers, as they have the ability to stabilize emulsions by aligning themselves on the interface between the non-polar and polar liquids, with their polar ends in the polar liquid and their non-polar ends in the non-polar liquid. Amphiphile (from the Greek αμφις amphis both and φιλíα Philia: love friendship is a term describing a Chemical compound possessing both Surfactants are wetting agents that lower the Surface tension of a liquid allowing easier spreading and lower the Interfacial tension between two liquids SOAP (see below for name and origins is a protocol for exchanging XML -based messages over Computer networks normally using An emulsion ( IPA: /ɪˈmʌlʃən/ is a mixture of two Immiscible (unblendable liquids

Solvation

Main article: Solvation

During solvation, especially when the solvent is polar, a structure forms around it, which allows the solute-solvent interaction to remain stable. Solvation, commonly called dissolution, is the process of attraction and association of Molecules of a Solvent with molecules or Ions of a Solvation, commonly called dissolution, is the process of attraction and association of Molecules of a Solvent with molecules or Ions of a

When no more of a solute can be dissolved into a solvent, the solution is said to be saturated. In Chemistry, saturation has five different meanings In Physical chemistry, saturation is the point at which a Solution of a substance However, the point at which a solution can become saturated can change significantly with different environmental factors, such as temperature, pressure, and contamination. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Pressure (symbol 'p' is the force per unit Area applied to an object in a direction perpendicular to the surface For some solute-solvent combinations a supersaturated solution can be prepared by raising the solubility (for example by increasing the temperature) to dissolve more solute, and then lowering it (for example by cooling). The term supersaturation refers to a Solution that contains more of the dissolved material than could be dissolved by the Solvent under normal circumstances Solubility is the characteristic Physical property referring to the ability of a given substance the Solute, to dissolve in a Solvent. In Chemistry, a solution is a Homogeneous Mixture composed of two or more substances

Usually, the greater the temperature of the solvent, the more of a given solid solute it can dissolve. However, most gases and some compounds exhibit solubility that decrease with increased temperature. Such behavior is a result of an exothermic enthalpy of solution. In Thermodynamics, the word exothermic "outside heating" describes a process or reaction that releases Energy usually in the form of Heat, but The enthalpy of solution (or enthalpy of dissolution) is the Enthalpy change associated with the dissolution of a substance in a Solvent at constant pressure Some surfactants exhibit this behaviour. Surfactants are wetting agents that lower the Surface tension of a liquid allowing easier spreading and lower the Interfacial tension between two liquids The solubility of liquids in liquids is generally less temperature-sensitive than that of solids or gases.

Ideal solutions

Main article: ideal solution

Properties of an ideal solution can be calculated by the linear combination of the properties of its components. In Chemistry, an ideal solution or ideal mixture is a Solution in which the Enthalpy of solution is zero the closer to zero the enthalpy of In Mathematics, linear combinations are a concept central to Linear algebra and related fields of mathematics

If both solute and solvent exist in equal quantities (such as in a 50% ethanol, 50% water solution), the concepts of "solute" and "solvent" become less relevant, but the substance that is more often used as a solvent is normally designated as the solvent (in this example, water).

See also

• Molar solution
• Percentage solution
• Solubility equilibrium
• Stock solution
• Total dissolved solids is a common term in a range of disciplines, and can have different meanings depending on the analytical method used. A molar Solution is one that contains one mole of solute per Litre of solution In Biology, percentage solutions are often preferred to molar ones Solubility equilibrium is any type Chemical equilibrium between solid and dissolved states of a compound at saturation. In Chemistry, a stock solution is a large volume of a common Reagent, such as Hydrochloric acid or Sodium hydroxide, at a standardized Concentration Total Dissolved Solids (often abbreviated TDS) is an expression for the combined content of all Inorganic and organic substances contained in a liquid In water quality, it refers to the amount of residue remaining after evaporation of water from a sample.

References

• IUPAC Gold Book Definition