Express the desired volume in liters.

1L

400 mL X --------= 0.400 L

1000 mL

Multiply the normal concentration times the gram equivalent weight times the volume

expressed in liters to determine the amount of solute needed to prepare the solution.

10 Eq

40.0 g

-------- X -------- X 0.400 L = 160 g

L

Eq

c. **Example**. What is the Eq/L concentration of an AlPO4 solution that was

prepared by adding 120.0 grams of AlPO4 to a 250 mL flask and adjusting the volume to

the mark?

Solution. Read the problem carefully and determine the desired quantity.

Eq/L concentration.

Determine the GEW of the compound.

AlPO4

Al

27.0 X 1 = 27.0

P

31.0 X 1 = 31.0

O

16.0 X 4 = + 64.0

122.0 g/mol

122.0 g

mol

--------X -------- = 40.67 g/Eq

mol

3 Eq

Express the grams of solute as equivalents using the appropriate conversion

factor.

Eq

120.0 g X --------= 2.951 Eq

40.67 g

MD0837

4-6

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