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For example, in n z with z = i, tetration is achieved by using the principal branch of the natural logarithm; using Euler's formula we get the relation: i a + b i = e 1 2 π i ( a + b i ) = e − 1 2 π b ( cos π a 2 + i sin π a 2 ) {\displaystyle i^{a+bi}=e^{{\frac {1}{2}}{\pi i}(a+bi)}=e^{-{\frac {1}{2}}{\pi b}}\left(\cos {\frac ...
GCSE Bitesize was launched in January 1998, covering seven subjects. For each subject, a one- or two-hour long TV programme would be broadcast overnight in the BBC Learning Zone block, and supporting material was available in books and on the BBC website. At the time, only around 9% of UK households had access to the internet at home.
A titration curve is a curve in graph the x-coordinate of which represents the volume of titrant added since the beginning of the titration, and the y-coordinate of which represents the concentration of the analyte at the corresponding stage of the titration (in an acid–base titration, the y-coordinate usually represents the pH of the solution).
Some examples of primary standards for titration of solutions, based on their high purity, are provided: [4] Arsenic trioxide for making sodium arsenite solution for standardisation of sodium periodate solution (until Ph. Eur. 3, Appendix 2001 also for iodine and cerium(IV) sulfate solutions, since Ph. Eur. 4, 2002 standardised by sodium ...
Titres are sometimes expressed by the denominator only, for example 1:256 is written 256. [3] The term also has two other, conflicting meanings. In titration, the titer is the ratio of actual to nominal concentration of a titrant, e.g. a titer of 0.5 would require 1/0.5 = 2 times more titrant than nominal. This is to compensate for possible ...
For example, by comparing the absorbance values of a solution with an unknown concentration to a series of standard solutions with varying concentrations, the concentration of the unknown can be determined using Beer's Law. Any form of spectroscopy can be used in this way so long as the analyte species has substantial absorbance in the spectra ...
The chief advantage over other types of titration is the selectivity offered by the electrode potential, as well as by the choice of titrant. For instance, lead ion is reduced at a potential of -0.60 V (relative to the saturated calomel electrode ), while zinc ions are not; this allows the determination of lead in the presence of zinc.
Thermometric iodometric titrations employing thiosulfate as a titrant are also practical, for example in the determination of Cu(II). In this instance, it has been found advantageous to incorporate the potassium iodide reagent with the thiosulfate titrant in such proportions that iodine is released into solution just prior to its reduction by ...