8153

• UCREFRP Catalog Number: 8153
• Author: Jacobs, e. L. W.
• Title: Editor
• USFW Year: Series
• USFW - Doc Type: 1989
• Copyright Material: YES

r
Eh-pH Diagram Se
E = 10-`M
HSe04
HZSe03
SeOy
HSe03
Se
Se03 -
HZS
HSe
2
0
PH
Fig. 1-1. An Eh-pH diagram for the Se-H2O system.
using the data in Wagman et al. (1982) and Elrashidi et al. (1987) and is similar
to the diagrams presented in Geering et al. (1968) and Neal et al. (1987). The
chemical characteristics of Se, including information on acidity constants,
solubility products, and qualitative reaction rates, is summarized in a schemat-
ic diagram in Fig. 1-2. A brief review in terms of each oxidation state and
GEOCHEMISTRY & OCCURRENCE OF SELENIUM 3
t.a
1,2
0,8
0.4
Eh
0.0
-0,4
-0.8
-1,