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Normality Formula:
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Normality (N) is a measure of concentration in chemistry that expresses the number of gram equivalents of solute per liter of solution. It is particularly useful in acid-base chemistry and redox reactions where the number of reactive particles matters.
The calculator uses the normality formula:
Where:
Explanation: The formula converts molar concentration to normal concentration by multiplying by the number of reactive hydrogen or hydroxide ions the compound can donate or accept.
Details: Normality is crucial in titration calculations, acid-base reactions, and redox reactions where the equivalent weight matters more than molecular weight. It provides a direct measure of reactive capacity.
Tips: Enter molarity in mol/L and acidity/basicity as a whole number representing the number of H+ or OH- ions. For acids, n equals the number of acidic protons. For bases, n equals the number of OH- groups.
Q1: What is the difference between molarity and normality?
A: Molarity measures moles per liter, while normality measures equivalents per liter. Normality accounts for the reactive capacity of the solute.
Q2: How do I determine the value of n?
A: For acids, n is the number of acidic hydrogen atoms. For bases, n is the number of hydroxide ions. In redox reactions, n is the number of electrons transferred.
Q3: When should I use normality instead of molarity?
A: Use normality for acid-base titrations, precipitation reactions, and redox reactions where equivalent weights are important. Use molarity for general concentration measurements.
Q4: What are some examples of n values?
A: HCl (n=1), H₂SO₄ (n=2), NaOH (n=1), Ca(OH)₂ (n=2), H₃PO₄ (n=3 for triprotic acid).
Q5: Can normality be converted back to molarity?
A: Yes, using the formula M = N ÷ n, where n is the same acidity/basicity factor used in the original calculation.