Lab Report Stoichiometry

Purpose

The purpose of this experiment was to evaluate the stoichiometric relationship between the testing agents and to identify the products formed. The relationship was found by completing three acid and base neutralization reactions using phosphoric acid, which is a triprotic acid, with different volumes of sodium hydroxide.

Introduction

Procedure

Phosphoric acid solution with a volume of 1.00 mL and a molarity of 6.00 M was transferred into a 125-mL Erlenmeyer flask using a volumetric pipette. Sodium hydroxide solution with a volume of 6.00 mL and a molarity of 3.00 M was transferred into a 50 mL beaker using a volumetric pipette. While swirling the phosphoric acid solution in the Erlenmeyer flask, the sodium hydroxide solution was added to it a few drops at a time using a disposable plastic pipette. The After all the sodium hydroxide was transferred, the flask was rinsed with 2 mL of deionized water and added to the flask with the reaction mixture and swirled for an additional minute. A clean, dry evaporating dish with a watch glass was then weighed and recorded to 0.001 g. The reaction mixture was then transferred to the evaporating dish. The flask was then rinsed with 2 mL of deionized water and added to the evaporating dish containing the reaction mixture.

The evaporating dish was placed on top of the wire gauze and covered with the watch glass. The Bunsen burner was used to heat the water to a boil until the water had evaporated, leaving a dry, white solid (salt). The evaporating dish with the watch glass containing the salt residue was then weighed and recorded to 0.001 g. The mass of the evaporating dish and watch glass containing the salt residue was subtracted from the mass of just the evaporating dish and watch glass which gave the mass of the