## THEORY:

Reaction HCl + NaOH——-> NaCl + H₂O

Ionically, H^{+} + OH^{–} ————> H₂O

The normality strength of the alkali can be determined by titrating it against the standard acid, and by using the normality equation.

V₁N₁ = V₂N₂

Where, V₁ = volume of acid V₂ = volume of alkali

N₁ = normality of acid N₂ = normality of alkali

= N₂ =V₁N₁/V₂

## APPARATUS :

1) Burette

2) Pipette

3) Conical flask

4) Burette stand

5) Clamps

## CHEMICALS:

1) Methyl orange indicator

## PROCEDURE :

Proceed exactly as in expt 2, and tabulate the results as follows

## RESULTS:

Solution taken in the burette = HCl acid

Alkali taken for each titration = 10 ml

Indicator used = methyl orange

End point = from yellow to light pink

Normality of standard acid =N/10 (f = 1.10)

No. of obs. | Initial reading | Final reading | Vol of acid (ml) | Means |

1 | 10.6 ——> | (approx) | ||

2 | 10.4 | |||

3 | 10.3 | 10.3 | ||

4 | 10.3 |

## CALCULATIONS :

Acid Alkali

V₁ = 10.3 ml V₂ = 10 ml

N₁ = N/10 (f = 1.10) N₂ = ?

By applying the normality equation,

V₁N₁ = V₂N₂

10.3 ml x N/10 x 1.10 = 10 ml x N₂

N₂ = 10.3 × N × 1.10/10 × 10

=N/10 (f=1.133)