Hach-Lange TITRALAB 840_845 Reference Manual - Manual (Page 141)

Titra Lab ® TitraLab 840 and 845 Reference Manual
Page 141
Reaction X Exc.
+ Y Titr Enter stoichiometric coefficients for the reaction between the excess
reagent and the titrant when the following units have been selected:
• Excess titrant unit (M, mM),
or
• Titrant unit (M, mM)
To determine the X and Y stoichiometric coefficients:
The reaction is: X Exc + Y Titr ->
where:
• 1 mole of titrant gives X eq of titrant
• 1 mole of excess reagent gives Y eq of excess reagent
To balance the reaction, Y mole(s) of titrant are required to titrate X
mole(s) of excess reagent.
Example:
Titrant
sodium hydroxide (NaOH). 1 mole of NaOH gives 1 eq of NaOH.
Excess reagent
citric acid (C
3
H
5
0 (COOH)
3
). 1 mole of citric acid gives 3 eq of citric
acid.
Reaction
3 NaOH +1 C
3
H
5
O(COOH)
3
-> C
3
H
5
0 (COONa)
3
+ 3H
2
O
Enter
Reaction = 1 Exc + 3 Titr ->
Enter in:
Edit method > Results (for back titration methods)
Range available:
(1 to 20) Exc + (1 to 20) Titr ->
When you enter the coefficients of X Exc + Y Titr ->, please also
check the coefficients of the X Smp + Y Exc -> equation (line
above in the Results screen).
X of Smp is always equal to Y of Titr: it may be necessary to
change the Y coefficient of the X Smp + Y Exc -> equation.
Refer to "Appendix 3: Result calculations", page 205 .