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It is an acid being neutralized by a base (or vice versa), usually with some kind of indicator or color change, and a pH meter to check pH levels along the way. For example, you would use it to find the molarity of HCl with a known concentration of NaOH, and use phenolphthalein as an indicator.

Take a known aliquot of your unknown concentration (25mL for the sake of the example), and add some indicator to it. Titrate with the known concentration of base until the phenolphthalein turns pink - this means it is a basic solution now. At a pH of 7, moles of acid = moles of base. You know your volumes of both acid and base, you know the concentration of one, and with all of that information, the unknown concentration can be calculated!

2006-10-14 18:33:18 · answer #1 · answered by Anonymous · 0 0

Titration is a standard laboratory method of quantitative/chemical analysis which can be used to determine the concentration of a known reactant.

Because volume measurements play a key role in titration, it is also known as volumetric analysis. A reagent, called the titrant, of known concentration (a standard solution) and volume is used to react with a measured quantity of reactant (Analyte).

Using a calibrated burette to add the titrant, it is possible to determine the exact amount that has been consumed when the endpoint is reached. The endpoint is the point at which the titration is stopped.

This is classically a point at which the number of moles of titrant is equal to the number of moles of analyte, or some multiple thereof (as in di- or tri- protic acids).

In the classic strong acid-strong base titration the endpoint of a titration is when the pH of the reactant is just about equal to 7, and often when the solution permanently changes color due to an indicator. There are however many different types of titrations (see below).

Many methods can be used to indicate the endpoint of a reaction; titrations often use visual indicators (the reactant mixture changes colour).

In simple acid-base titrations a pH indicator may be used, such as phenolphthalein, which turns (and stays) pink when a certain pH is reached or exceeded.

Methyl orange can also be used, which is red in acids and yellow in alkalis.

Not every titration requires an indicator. In some cases, either the reactants or the products are strongly coloured and can serve as the "indicator". For example, an oxidation-reduction titration using potassium permanganate (pink/purple) as the titrant does not require an indicator. When the titrant is reduced, it turns colourless. After the equivalence point, there is excess titrant present. The equivalence point is identified from the first faint pink colour that persists in the solution being titrated.

Due to the logarithmic nature of the pH curve, the transitions are generally extremely sharp, and thus a single drop of titrant just before the endpoint can change the pH significantly — leading to an immediate colour change in the indicator. That said, there is a slight difference between the change in indicator color and the actual equivalence point of the titration. This error is referred to as an indicator error, and it is indeterminate.

2006-10-14 18:34:15 · answer #2 · answered by Glenn 2 · 0 0

NMR might want to have a tricky time determining concentrations, by using similarity of the water and the hydrogen peroxide protons. NMR in a number of of situations supplies poor analytical effects besides, in evaluation to many different analytical concepts. I imagine you would possibly want to locate thanks to apply HPLC effectively, notwithstanding it would want to nevertheless be a lot less complicated to do a titration.

2016-12-04 20:30:41 · answer #3 · answered by Anonymous · 0 0

Ugh, I used to hate doing that crap.

2006-10-14 18:38:50 · answer #4 · answered by mdigitale 7 · 0 0

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