Seawater
==========================

The chemical compositions varies. The compounds compositions in this doc
is an approximate and representative. 

================= ===============
compounds         concentration
================= ===============
:math:`NaCl`      0.50M
:math:`MgSO_4`    0.03M
:math:`NaHCO_3`   0.01M
:math:`KCl`       0.01M
:math:`CaCl_2`    0.01M
================= ===============

salinity: 31 to 38 g/L

PH: 7.5 to 8.5