In chemistry Chemistry (from Arabic:الكيم Latinized: chem , meaning "earth") is the science concerned with the composition, behavior, structure, and properties of matter, as well as the changes it undergoes during chemical reactions. It is a physical science for studies of various atoms, molecules, crystals and other aggregates of matter whether, a solution is a homogeneous Homogeneous mixtures are a type of mixture that are perfectly uniform in their composition, as opposed to heterogeneous mixtures mixture In chemistry, a mixture is when two or more different substances are mixed together but not combined chemically. The molecules of two or more different substances are mixed in the form of solutions, suspensions, and colloids composed of two or more substances. In such a mixture, a solute In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is dissolved in another substance, known as a solvent is dissolved in another substance, known as a solvent The most common solvent in everyday life is water. Most other commonly-used solvents are organic chemicals. These are called organic solvents. Solvents usually have a low boiling point and evaporate easily or can be removed by distillation, leaving the dissolved substance behind. To distinguish between solutes and solvents, solvents are usually. Usually, the substance present in a greater amount is considered as the solvent. Solutions may have multiple solvents. Gases Pressuretotal = Pressure1 + Pressure2 + ... + Pressuren may dissolve Solvation, also sometimes called dissolution, is the process of attraction and association of molecules of a solvent with molecules or ions of a solute. As ions dissolve in a solvent they spread out and become surrounded by solvent molecules in liquids, for example, carbon dioxide Carbon dioxide is a chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom. It is a gas at standard temperature and pressure and exists in Earth's atmosphere in this state. CO2 is a trace gas being only 0.038% of the atmosphere or oxygen Oxygen (pronounced /ˈɒksɨdʒɨn/, OK-si-jin, from the Greek roots ὀξύς (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O. It is a member of the chalcogen group on the periodic table, and is a highly in water. 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 An alloy is a partial or complete solid solution of one or more elements in a metallic matrix. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may be homogeneous in distribution depending on thermal history. Alloys usually have different properties from those of the and certain minerals A mineral is a naturally occurring solid formed through geological processes that has a characteristic chemical composition, a highly ordered atomic structure, and specific physical properties. A rock, by comparison, is an aggregate of minerals and/or mineraloids, and need not have a specific chemical composition. Minerals range in composition and polymers containing plasticizers Plasticizers or dispersants are additives that increase the plasticity or fluidity of the material to which they are added, these include plastics, cement, concrete, wallboard, and clay. Although the same compounds are often used for both plastics and concretes the desired effect is slightly different. The worldwide market for plasticizers in 2004. The ability of one compound Compound when applied to a human habitat refers to a cluster of buildings in an enclosure, having a shared or associated purpose, such as the houses of an extended family. The enclosure may be a wall, a fence, a hedge or some other structure, or it may be formed by the buildings themselves, when they are built around an open area or joined to dissolve in another compound is called solubility Solubility is the property of a solid, liquid, or gaseous chemical substance called solute to dissolve in a liquid solvent to form a homogeneous solution. The solubility of a substance strongly depends on the used solvent as well as on temperature and pressure. The extent of the solubility of a substance in a specific solvent is measured as the. The physical properties of compounds such as melting point The melting point of a solid is the temperature range at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. When considered as the temperature of the reverse change from liquid to solid, it is referred to as the freezing point. Because of the ability of some substances to supercool, and boiling point The boiling point of an element or a substance is the temperature at which the vapor pressure of the liquid equals the environmental pressure surrounding the liquid. A liquid in a vacuum environment has a lower boiling point than when the liquid is at atmospheric pressure. A liquid in a high pressure environment has a higher boiling point than change when other compounds are added. Together they are called colligative properties Colligative properties are properties of solutions that depend on the number of molecules in a given volume of solvent and not on the properties of the molecules. Colligative properties include: lowering of vapor pressure; elevation of boiling point; depression of freezing point and osmotic pressure. Measurements of these properties for a dilute. 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. This can apply to any sort of chemical mixture, but most frequently the concept is limited to homogeneous solutions, where it refers to the amount of solute in the solvent. Examples include molarity, mole fraction, and parts per million (ppm).
Solutions should be distinguished from non-homogeneous mixtures such as colloids A colloid is a type of chemical mixture in which one substance is dispersed evenly throughout another. The particles of the dispersed substance are only suspended in the mixture, unlike in a solution, in which they are completely dissolved. This occurs because the particles in a colloid are larger than in a solution - small enough to be dispersed and suspensions In chemistry, a suspension is a heterogeneous fluid containing solid particles that are sufficiently large for sedimentation. Usually they must be larger than 1 micrometre. The internal phase is dispersed throughout the external phase (fluid) through mechanical agitation, with the use of certain excipients or suspending agents. Unlike colloids,. When a liquid is able to completely dissolve in another liquid the two liquids are miscible. Two substances that can never mix to form a solution are called immiscible.
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Examples of solutions
Many types of solutions exist, as solids Matter is generally found in three different forms: solid, liquid, and gas . The solid state of matter is characterized by a distinct structural rigidity and resistance to deformation (that is changes of shape and/or volume). Most solids have high values both of Young's modulus and of the shear modulus of elasticity. This contrasts with liquids or, liquids A liquid is one of three classical states of matter, the other two being solid and gas and gases The temperature of any physical system is related to the motions of the particles which make up the [gas] system. In statistical mechanics, temperature is the measure of the average kinetic energy stored in a particle. The methods of storing this energy are dictated by the degrees of freedom of the particle itself (energy modes). Kinetic energy can be both solvent and solute:
Solvation
Main article: SolvationDuring solvation, especially when the solvent is polar, a structure forms around it, which allows the solute-solvent interaction to remain stable.
When no more of a solute can be dissolved into a solvent, the solution is said to be saturated. However, the point at which a solution can become saturated can change significantly with different environmental factors, such as temperature, pressure, and contamination. 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).
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. Some surfactants exhibit this behaviour. The solubility of liquids in liquids is generally less temperature-sensitive than that of solids or gases.
Ideal solutions
Main article: Ideal solutionProperties of an ideal solution can be calculated by the linear combination of the properties of its components.
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
| Look up solution or solute in Wiktionary, the free dictionary. |
| Wikibooks has a book on the topic of Transwiki:Creating chemical solutions |
- Concentration
- Molar solution
- Percentage solution
- Solubility equilibrium
- Stock solution
- Aqueous solution
- Total dissolved solids is a common term in a range of disciplines, and can have different meanings depending on the analytical method used. In water quality, it refers to the amount of residue remaining after evaporation of water from a sample.
References
International Union of Pure and Applied Chemistry. "solution". Compendium of Chemical Terminology Internet edition.
- ^ Streitwieser, Andrew; Heathcock, Clayton H., Kosower, Edward M. (1992). Introduction to Organic Chemistry (4th ed. ed.). Macmillan Publishing Company, New York. ISBN 0-02-418170-6.
- ^ WikiPremed > Coordination Chemistry Retrieved on July 2, 2009
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Categories: Solutions | Homogeneous chemical mixtures | Alchemical processes | Physical chemistry | Colloidal chemistry | Dosage forms
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Q. I forgot how to do this. I haven't been in school in ages and my daughter needs to know.
Asked by ods - Wed Sep 5 20:41:24 2007 - - 4 Answers - 0 Comments
A. start with the smallest number it is divisable by besides one. This is how to do a factor tree. If thats what you want. All the factors are 1,5,7, and 35 35 __ 5|7 = 35 the middle thing represents a vertical line to separate 5 and 7. You would want to make it like a capital T. Without so much space between the 35 and the factors but i cant do it on here. Believe it or not...thats it.
Answered by Prisoner of Grace - Wed Sep 5 20:52:33 2007
