b. Example 2. What is the Eq/L concentration of a 5.0 g/dL CaCO3 solution?
Solution. Read the problem carefully and determine the desired unit of
concentration.
Determine the GEW of the compound.
CaCO3
Ca 40.1 X 1 = 40.1
C
12.0 X 1 = 12.0
O 16.0 X 3 = + 48.0
100.1 g/mol
100.1 g
1 mol
-------- X ------ = 50.05 g/Eq
mol
2 Eq
Use the GEW and the appropriate volume conversion factor to express the
Eq/L concentration.
5.0 g
1 Eq
10 dL
------X -------- X ------ = 1.0 Eq/L
dL
50.05 g
1L
5-4.
CONVERTING FROM mol/L TO Eq/L AND FROM Eq/L TO mol/L
The conversion is based on the use of TPIV expressed as Eq/mol and used as
an appropriate factor.
a. Example 1. What is the mol/L concentration of a 4 Eq/L Ba(OH)2 solution?
Solution. Read the problem carefully and determine the desired unit of
concentration.
Molarity (mol/L).
Determine the number of equivalents per mole of compound and use it as an
appropriate conversion factor to express the solution in the desired units.
4.0 Eq
1 mol
------ X -------- = 2.0 mol/L
L
2 Eq
MD0837
5-5