Alkalinity Calculator

Version 2.22
[22-Sep-2012]

Version History
Methods
Speciation Criteria
Reporting Tips
Acid Lot Info
FAQ
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Input acidimetric titration data and other information in the form below. Fields shown in red are required. The Alkalinity Calculator will analyze the titration curve and calculate the alkalinity or acid neutralizing capacity (ANC) of the sample using one or more of several different methods. Alkalinity is for filtered samples, while ANC is for unfiltered samples. The results will be displayed in tabular and graphical form.

The Alkalinity Calculator also is available in a stand-alone version.

Send comments, questions, and suggestions to sarounds@usgs.gov. Please send me any datasets that appear to cause problems for the Alkalinity Calculator.

Note: I see that javascript is not currently enabled in your browser. That's okay -- the Alkalinity Calculator will work without javascript. I invite you to enable javascript for this page, however, because the interface utilizes javascript to clarify and simplify data input.

Sample Information

Site Name:

Site ID:

Collection Date:

Collection Time:

Titration Information

Analyst:

Analysis Date:

Analysis Time:

Sample Temperature:

^oC [help]

Specific Conductance:

µS/cm [help]

Sample Volume:

Filtered Sample?:

Acid Concentration:

Specify other acid conc.:

Acid Lot Number:

Acid Correction Factor:

[help]

Acid Expiration Date:

Stirring Method:

Titration Type:

Digital titrator
Buret titration

Titration Data:

Enter two columns of data:
Order:
Data must be delimited by a comma or by one or more spaces.
You may "paste" your data into this form with the mouse.

Digital titrator: (counts)
Titrant volumes are specified in "counts" and are assumed
to come from a Hach digital titrator (800 counts per mL).

Buret titration: (mL)
Titrant volumes from a buret titration are specified in
milliliters (mL) of acid added.

Comments:

Titration Analysis

Analysis Methods:

Check one or more of the analysis methods you want to use:

Inflection point method
Gran function plot method
Theoretical carbonate titration curve method
Fixed endpoint:	Carbonate: pH = Bicarbonate: pH =

Speciation Method:

The advanced speciation method will be used for the calculation of carbonate
and bicarbonate concentrations; the simple mass-balance speciation method is
deprecated and no longer available.

The calculation may take a minute or two.

Note: The specific conductance is used to estimate the ionic strength of the sample. Ionic strength and sample temperature are used to calculate the equilibrium dissociation constants of water and carbonic acid, which are then used in the calculation of hydroxide, carbonate, and bicarbonate concentrations. If you know the sample's temperature and specific conductance, please input them. If these data are unavailable, default values will be assumed.

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U.S. Department of the Interior | U.S. Geological Survey
URL: https://or.water.usgs.gov/alk/index.html
Page Contact Information: Stewart Rounds
Page Last Modified: Friday - Jul 5, 2024 at 18:10:01 EDT