Titration Experiment

Experiment 1

Investigation of the suitability of indicators and instrumental detection of equivalence points in acid – base titrations.

Objectives

To determine the pH titration curve for both strong acid – base titration and weak – acid base titration. To determine the suitability of phenolphthalein and screened methyl orange as acid base indicators for detecting the end points of acid-base titrations.

Materials

Chemicals

0.1M Hydrochloric acid, 0.1M Acetic acid, 0.1M Sodium hydroxide, 0.1M Ammonium hydroxide, phenolphthalein, screened methyl orange, methyl orange.

Apparatus

100ml beakers, 250ml conical flasks, 50ml burettes, 25ml pipettes, pipette fillers, filter funnels, pH meters.

Introduction

Indicator is normally a weak organic acid or base that has discretely different colours in its protonated and deprotonated figures. They are four sorts of acid base titration : strong acid - weak base titration, weak acid – strong base titration, weak acid - weak base titration and strong acid – strong base titration. Acid and base together are colourless in nature. Indicators are utilized as a part of acid base titration in order to obtain the equivalence points and end points. In this experiment, they are only strong acid - weak base titration and weak acid - strong base titration is examined.

Procedure

25ml of 0.1M hydrochloric acid is pipetted into a 250ml conical flask. 2-3 drops of the indicator, phenolphthalein is put into the solution in the conical