When Using The Digital Titrator For Your Buret Method - Hach DR2400 Manual

Chemical Analysis
Chemical Analysis
Page 50
3. When using the Digital Titrator for your buret method, note the number of
digits required for a sample titration. To convert the digits required to the
equivalent number of milliliters for a buret method, calculate:
Equivalent Buret Milliliters =
If the sample size was changed, adjust the equivalent buret milliliters
accordingly. If the sample size was increased, reduce the equivalent buret
milliliters; if the sample size was reduced, increase the equivalent buret
milliliters. Multiply the equivalent buret milliliters by any normally used factors
to calculate concentration in oz./gal, g/L, etc.
Example: Adapt a buret procedure that normally requires about 20 mL of a 0.4 N
titrant to the Digital Titrator. Try an 8.0 N titration cartridge. The first equation
above gives:
×
0.4 20
Digits Required = ------------------------------------ -
8.0
Because this would use excessive titrant, reduce the sample size to one-fourth its
normal size to reduce the digits required to 200, well within the recommended
range.
Upon completion of the titration using the smaller sample size, calculate the
equivalent buret milliliters by the second equation above.
If 205 were the digits required:
Equivalent Buret Milliliters =
Multiply the resulting 5.13 mL by four to account for the reduction in sample
size and give the true equivalent buret milliliters of 20.5 mL. If the buret method
called for multiplying the number of milliliters of titrant by a factor to calculate
the concentration of a sample component, then multiply 20.5 by that factor.
Bismuth Nitrate, 0.0200 M
CDTA, 0.800 M, HexaVer
Ceric Standard Solution, 0.5N
EDTA, 0.0800 M, TitraVer
EDTA, 0.142 M
EDTA, 0.714 M
EDTA, 0.800 M, TitraVer
FEAS, ferrous ethylenediammonium sulfate, 0.00564 N
Hydrochloric Acid, 8.00 N
Iodate-Iodide, potassium, 0.3998 N
Iodate-Iodide, potassium, 1.00 N
Magnesium Chloride, 0.0800 N
Mercuric Nitrate, 0.2256 N
Mercuric Nitrate, 2.256 N
Mercuric Nitrate, 2.57 N
PAO, phenylarsine oxide, 0.00451 N
N c
×
--------------------- -
Digits Required
×
800 N t
×
800
= 800 digits
×
205 8.0
----------------------- - = 5.13 mL
×
800 0.4
Table 12
Description Cat. No.
24345-01
14403-01
22707-01
14364-01
14960-01
14959-01
14399-01
22923-01
14390-01
14961-01
22944-01
20625-01
14393-01
921-01
23937-01
22599-01
5940022ChemAnal.fm