Question

What formula is used to calculate the concentration of base in titration?

Answer 1

The concentration of base in a titration is calculated using the formula: concentration of base (M) = moles of acid / volume of base (L). This calculation is based on the stoichiometry of the neutralization reaction, typically in a one-to-one mole ratio, and is performed after achieving neutrality as indicated by an indicator or pH meter.

Step-by-step explanation:

To calculate the concentration of base in a titration, a known volume and concentration of an acid are titrated against the base with an unknown concentration. The formula used for this calculation is concentration of base (M) = moles of acid / volume of base (L). This equation comes from the stoichiometry of the neutralization reaction, which for monoprotic acids and bases is typically a one-to-one mole ratio.

Using the stoichiometry of the neutralization reaction, which in a simple acid-base reaction like HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l), is 1:1, you can determine the moles of base that react with the moles of acid. The moles of acid are calculated by multiplying the concentration of the acid by the volume of acid (in liters). Once neutrality is achieved, indicated by a color change of the indicator or a specific reading on a pH meter, the volume of base used is noted. The moles of acid originally present in the solution are equal to the moles of base since they react in a 1:1 ratio. This allows the calculation of the base concentration using the titrant volume and the known concentration of the acid.

Answer 2

The unknown base concentration can be calculated from

• Cb = (Cₐ * Vₐ) / Vb

Step-by-step explanation:

An acid–base titration is a quantitative method of analysis for the determination of the concentration of an acid or base by neutralizing it with a standard solution (solution of known concentration) of base or acid.

At the equivalence point, when all unknown base neutralized by standard acid solution

the following is applied

No. of equivalent of acid = No. of equivalent of base

Cₐ * Vₐ = Cb * Vb

where,

Cₐ: is the concentration of standard acid solution (known).

Vₐ: is the volume of acid that neutralizes the base (known).

Cb: is the unknown base concentration (unknown).

Vb: is the volume of base that neutralized with the acid (known).

So, the unknown base concentration can be calculated from

• Cb = (Cₐ * Vₐ) / Vb