How to Calculate a Milliequivalent

Formula

• 1

  Use the formula mEq = AW / (V x 1000) to calculate the milliequivalent. AW = atomic weight (g) and V = valence.

• 2

  Select the element and identify the atomic weight (AW) and valence (V). For illustration purposes, potassium (K) is AW = 39.0983 g and V = 1.

• 3

  Insert the values into the formula mEq = AW / (V x 1000) and calculate. For potassium: mEq = 39.0983 g / (1 x 1000), so mEq = 0.0390983 g.

• 4

  For compounds, calculate the total atomic weight and identify the lowest valence. For example, potassium chloride (KCl):

  Potassium (K)

  AW = 39.0983 g

  V = 1

  Chloride (Cl)

  AW = 35.4532 g

  V = 5

  The lowest valence is 1 (potassium).

• 5

  For compounds, insert the values into the formula mEq = Total AW / (V x 1000) and calculate. For potassium chloride:

  mEq = (KAW + ClAW) / (V x 1000)

  mEq = (39.0983 g + 35.4532 g) / (1 x 1000)

  mEq = 74.5515 g / 1000

  mEq = 0.0745515 g