wtw PhotoLab Spektral Operating Instructions Manual page 30

Instructions for the Preparation of Standard Solutions
Standard solution of
nonionic surfactants
Preparation of a standard solution:
Dissolve 1.00 g of Triton
water in a calibrated or conformity-checked 1000-
ml volumetric flask and make up to the mark with
distilled water. The stock solution prepared accor-
ding to this procedure has a concentration of
1000 mg/l nonionic surfactants.
Further investigational concentrations may be
prepared from this stock solution by diluting
accordingly.
Stability:
When stored in a cool place (refrigerator), the
stock solution remains stable for one week. The
diluted investigational solutions must be used
immediately.
Reagents required:
1.12298.0101 Triton
1.16754.9010 Water GR for analysis
XXVIII
®
X-100 with distilled
®
X-100
Standard solution of
volatile organic acids
Preparation of a standard solution:
Dissolve 3.40 g of sodium acetate trihydrate GR
with distilled water in a calibrated or conformity-
checked 1000-ml volumetric flask and make up to
the mark with distilled water. The stock solution
prepared according to this procedure has a
concentration of 1500 mg/l acetic acid.
Stability:
When stored in a cool place (refrigerator), the
stock solution remains stable for one week.
Reagents required:
1.06267.0500 Sodium acetate trihydrate GR
for analysis
1.16754.9010 Water GR for analysis
Release 05/04