10
POTASSIUM • SMART3 COLORIMETER
Tetraphenylboron Method Code 3639-SC
QUANTITY
CONTENTS
CODE
30 mL
*Sodium Hydroxide, 1.0N
*4004WT-G
5 g
*Tetraphenylboron Powder
*6364-C
1
Spoon, 0.05 g, plastic
0696
*WARNING:
Reagents marked with an * are considered to be potential health hazards.
To view or print a Safety Data Sheet (SDS) for these reagents go to www.lamotte.com.
Search for the four digit reagent code number listed on the reagent label, in the contents
list or in the test procedures. Omit any letter that follows or precedes the four digit code
number. For example, if the code is 4450WT-H, search 4450. To obtain a printed copy,
contact LaMotte by e-mail, phone or fax.
Emergency information for all LaMotte reagents is available from Chem-Tel
(US, 1-800-255-3924) (International, call collect, 813-248-0585).
RANGE:
0.0–10.0 ppm Potassium
MDL:
0.8 ppm
METHOD:
Potassium reacts with sodium tetraphenylborate to form a
colloidal white precipitate in quantities proportional to the
potassium concentration.
SAMPLE HANDLING
& PRESERVATION:
Store samples in polyethylene bottles, not in soft glass
where leaching of potassium from the glass may occur.
Samples may be acidi
fi
ed to pH 2 with nitric acid, but
should be neutralized before analyzing.
INTERFERENCE:
Calcium and magnesium interfere at very high
concentrations. Check for stray light interference (see p. 69).
PROCEDURE
1. Press and hold
until colorimeter turns on.
2. Press
ENTER
to select
TESTING MENU
.
3. Select
ALL TESTS
(or another sequence containing
085 Potassium
) from
TESTING MENU
.
4. Scroll to and select
085 Potassium
from menu.
5. Rinse a clean tube (0290) with sample water. Fill to the 10 mL line with
sample.
6. Insert tube into chamber, close lid and select SCAN BLANK.
7. Remove tube from colorimeter. Add 4 drops of *Sodium Hydroxide, 1.0N
(4004WT). Cap and mix.
