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O pH tube O 2 pH comparitors (black) O wide range indicator
O titrator O sulfuric acid (red cap) O Alk. Pot. I. Azide
O Manganese sulfate O Thiosulfate O titration flask
O thermometer O Secchi disk O Cond. Tester works
O plastic beaker
O conductivity/TDS standard or standardize at school first.
the 3rd time. Add 10 drops of wide-range indicator. Invert 10 times. Compare to the colors in the black comparators and read pH to the 1/10 s. Record the pH value.
a)Remove the lids from the twin sample bottles.
b)Hold both bottles in the same hand and rinse the bottles twice.
c)Fill both bottles with the same hand w/o getting bubbles…make sure the bottles are over the top full.
d)Cap the bottles.
e)Remove the caps of both bottles.
f)Add 8 drops of alkali potassium iodide azide and 8 drops of manganese sulfate.
g)Cap and invert 10 times. Let settle to shoulders.
h)Uncap and add 8 drops of sulfuric acid. (red cap)
i)Invert 10 times.
j)Let settle until no particles can be seen.
k)Uncap titration tubes. (Larger clear cylinders w/ caps)
l)Rinse with fluid from step j twice, then fill to the line.
m)Fill titrator (hypodermic) to the 0 mark with thiosulfate.
n)Make sure to remove any bubbles.
o)Place titrator in cap hole and replace cap.
p)Add 3 drops from titrator, then uncap and add 8 drops of of starch indicator. (white cap)
q)Recap with titrator still in hole.
r)Add one drop and swirl to check color.
s)Repeat step r until one drop makes the solution turn clear.
t)Read titrator value in ppm of oxygen.
u)Repeat titration until you have 2 values within .6 of each other. Record those 2 values and their average on your data page.
11. View river/lake site and record all other information on the data sheet.
12. Turn off conductivity tester and pack up kit. Take waste disposal and pour it into a sink somewhere.