Titration is a method of quantitative chemical analysis that is commonly used in the laboratory to determine the concentration of the reactants . Because volume measurements play an important role in titration , it is also recognized technique with volumetric analysis . Titrimetric analysis is one of the main part of analytical chemistry and stoichiometry calculations based on the relationship of chemical reactions . Titrimetric method of analysis based on chemical reactions such as : aA + tT → outcomes with information : ( a) molecules react with the analyte A ( t ) T. reactant molecules Reagent T , called the titrant , is added in small increments , usually from a burette , in the form of solution of known concentration . The latter solution is called the standard solution and the concentration is determined by a process of standardization . The addition of titrant was continued until the number of T which is equivalent to A has been added . So said baha titrant equivalence point has been reached . In order to know when to stop adding titrant , chemists can use a chemical substance , called indicators , which bertanggap the presence of excess titrant with discoloration . Acid-base indicator is made of weak organic acids or bases , which have distinct colors when in a state of dissociation or not . This color change may or may not trejadi right at the equivalence point . Point titration when the indicator changes color is called the end point . It is certainly a hope , that there is as close to the end point of the equivalence point . Selecting indicators to make two points coincident ( or hold a correction for the difference between the two ) is one important aspect of titrimetric analysis . The term titration ntuk process involves measuring the volume of titrant required to reach the equivalence point . Over the years the term commonly used volumetric analysis than titrimetric . However, in terms of strict , titrimetric better term , because the volume measurements need not be limited by titration . In this particular analysis , for example , one can measure the volume of gas .A reagent is referred to as peniter [ 1 ] , which is known concentration ( a standard solution ) and used to react at atmospheric dititer solution [ 2 ] whose concentration is unknown . By using a calibrated burette to add peniter , it is possible to determine the exact amount of solution needed to reach the end point . The end point is the point at which the titration is complete , as determined by the indicator . Ideally, the indicator will change color when the equivalence point - where the volume of peniter added to certain mole is equal to the value of the mole dititer solution . In strong acid-base titration , the end point of the titration is the point when the pH of the reactant nearly 7 , and usually when the solution changes color to pink because of the pH indicator phenolphthalein . In addition to acid-base titration , there are also other types of titration .Many methods can be used to indicate the end point of the reaction ; titrations typically use visual indicators ( the reactant solution changes color ) . In simple acid-base titration , pH indicators can be used , for example is phenolphthalein , where phenolphthalein will change color to pink when the solution reaches a pH of about 8.2 or pass . Another example of a pH indicator that can be used is methyl orange , which turns red in acid and yellow in alkaline solution .Not every titration requires an indicator . In some cases , both the reactants and products have had a contrasting color and can be used as an " indicator " . For example , using potassium permanganate redox titration ( pink / purple ) as peniter not need indicators . When peniter reduced , the solution will be colorless . Upon reaching the equivalence point , there is a residual excess peniter in solution . Equivalence point is identified at the time of the emergence of the first pink color ( due to the excess permanganate ) in a solution that is being dititer .Due to the logarithmic nature of the pH curve , making color transitions are very sharp ; thus , one drop peniter at almost reach the endpoint can change the pH value significantly - that there was a change in the color of the indicator directly . There is a slight difference between the color change indicator and the actual equivalence point in the titration . This error is referred to as an error indicator , and a big mistake can not be determined .Email This BlogThis Share to Twitter Share to FacebookPost Home0 comments :
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