tech

Colorimetric
There are two basic types of colorimetric tests:
Tests which determine the concentration of a substance are based on Beer's Law. Simply stated, this says that the higher the concentration of a substance, the darker the color developed in the test, so more light is absorbed by the sample.
pH tests use an indicator which changes color with changes in the concentration of hydrogen ions, or the acidity of the solution.

Direct Reading Titrator
The Direct Reading Titrator is a 1.0 mL microburet calibrated to allow direct reading of the test result. Each Titrator has a specific range, but may be refilled to test higher concentrations .

Titrimetric
Titrimetric tests can be used to determine the concentration of a substance in a sample solution. After the sample is treated with an indicator, a standard titrant is added until a color change indicates a completed reaction. LaMotte offers four separate types of titration methods, allowing a choice of precision and convenience.

Automatic Buret
The self-zeroing automatic buret is calibrated from 0 to 10 mL in 0.1 mL increments. It is available with a squeeze valve (pinchcock), glass stopcock, or Teflon® stopcock.

Dropper Pipet
The drop count test uses a pipet to provide fast, precise measurements in the field. The number of drops used before the color change is multiplied by a given number to produce the test result.

Dropper Bottle
The dropper bottle test uses bottle tips which deliver a consistent standard drop size to add titrant to the sample. As with the drop count test, the number of drops used to complete the reaction is multiplied by a given equivalence factor to determine the concentration.

Electronic Methods
Electronic colorimeters measure the amount of light which travels through the reacted sample, and convert the measurement to an analog or digital reading as ppm or %T. In addition to colorimeters, LaMotte manufactures instruments to test pH, TDS/conductivity, dissolved oxygen, and turbidity.

Visual Methods (LaMotte offers several visual colorimetric comparators.)
The Octet Comparator and Octa-Slide contain eight color standards with built-in filters which eliminate optical distortion. The color standards in the Octet Comparator are arranged so that the sample can be compared to four standards at once. In the Octa-Slide, the standards are placed in a bar so that they can be compared to the sample individually.
There are two accessories which may be used with an Octet Comparator. The Bi-Color Reader (Code 2150) neutralizes sample color and/or turbidity to give more accurate readings. The Axial Reader (Code 2070) uses a mirror to extend the viewpath and intensify faint colors of low concentrations for easy distinction. Both accessories attach directly to the comparator and come with complete instructions for use.
LaMotte also offers an economical alternative to the Octet Comparator and Octa-Slide. The ColoRuler consists of plastic color standards mounted on a white plastic panel. The reacted sample is held against the panel and compared to the standards.

You may have a LaMotte test kit and require an extra copy of the Instructions or you might be interested in checking the test procedure before buying a kit, then you can click on the link bellow to download instructions for the required test kit.