Experiment 96

Objective

To prepare 250 ml of a 0.1 M (1/10 M) sodium carbonate (Na₂CO₃) standard solution.

Introduction

Sodium carbonate is a primary standard substance, ideal for preparing a standard solution due to its stability and purity. The molecular weight of Na₂CO₃ is 106 g/mol, calculated from its atomic composition: 10623×2+12+16×3=106.

To prepare 1000 ml of a 1 M Na₂CO₃ solution, 106 g of Na₂CO₃ is needed.For a 1000 ml solution of 0.1 M Na₂CO₃, 10.6 g of Na₂CO₃ is required.For a 250 ml solution of 0.1 M Na₂CO₃, 2.65 g of Na₂CO₃ is required.

Materials

Chemicals

·       Sodium carbonate (Na₂CO₃)

·       Distilled water

Apparatus

·       250 ml volumetric flask

·       Funnel

·       Weighing bottle

·       Weighing balance

·       Chemical balance

Reagent Preparation

·       Measure 2.65 g of sodium carbonate and place it in a 250 ml volumetric flask.

·       Add distilled water to reach a final volume of 250 ml.

Procedure

1.    Clean the 250 ml flask thoroughly.

2.    Dry the flask in an oven and allow it to cool.

3.    Weigh the empty, dry flask.

4.    Accurately weigh 2.65 g of sodium carbonate and add it to the flask.

5.    Add distilled