Titration Calculator
What is Titration?
Titration is an analytical procedure for determining the concentration of a substance in solution. In an acid-base titration, the amount of acid or base required to react with a known amount of base or acid is measured.
Equivalence Point: The point where the number of moles of acid equals the number of moles of base.
Basic Principle:
- Acid: H⁺ Donor
- Base: H⁺ Acceptor
- Neutralization: Acid + Base → Salt + Water
Formulas
Equivalence Point Condition:
n(Acid) = n(Base)
n(Acid) = n(Base)
Titration Formula:
c₁ · V₁ = c₂ · V₂
c₁ · V₁ = c₂ · V₂
Molar Amount:
n = c · V
n = c · V
Neutralization Reaction:
H⁺ + OH⁻ → H₂O
H⁺ + OH⁻ → H₂O
Examples
Hydrochloric Acid with Sodium Hydroxide
25 mL HCl (0.1 mol/L) requires 25 mL NaOH (0.1 mol/L) at equivalence point
25 mL HCl (0.1 mol/L) requires 25 mL NaOH (0.1 mol/L) at equivalence point
Weak Acid Titration
Acetic acid with NaOH: The equivalence point lies in the basic region (pH > 7)
Acetic acid with NaOH: The equivalence point lies in the basic region (pH > 7)
Determining Unknown Concentration
If 20 mL of an acid requires 25 mL 0.1 mol/L base: c(Acid) = 0.125 mol/L
If 20 mL of an acid requires 25 mL 0.1 mol/L base: c(Acid) = 0.125 mol/L
Buffer Titration
Titration of a buffer with strong acid or base shows different pH curves
Titration of a buffer with strong acid or base shows different pH curves
Technical Background
Types of Titrations
Acid-Base Titration: The most common type, used for determining acid or base concentrations.
Redox Titration: Based on electron transfer.
Complexometry: Uses complexing agents.
Precipitation Titration: Forms insoluble products.
Titration Procedure
- Prepare Sample: The substance is dissolved and placed in a flask with indicators
- Add Titrant: The standard solution is gradually added from a burette
- Observe Color Change: The indicator shows the equivalence point
- Record Volume: The consumed volume is noted
- Calculate: Using c₁V₁ = c₂V₂, the concentration is calculated
Indicators and Color Changes
| Indicator | pH Range | Color Change |
|---|---|---|
| Methyl Red | 4.5–6.2 | Red → Orange |
| Methyl Orange | 3.1–4.4 | Orange → Red |
| Phenolphthalein | 8.2–10.0 | Colorless → Pink |
| Bromothymol Blue | 6.0–7.6 | Yellow → Blue |
Sources of Error
- Inaccurate volume measurements
- Wrong choice of indicator
- Dilution or concentration changes during titration
- Uncalibrated glassware
- Pressure or temperature changes
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