Limiting Reactant Lab Report

Purpose
In this experiment, the limiting reactant of a chemical reaction and the percent by mass composition of a mixture were determined. An unknown salt mixture containing sodium phosphate and barium chloride dihydrate was added to water producing a mixture containing a solid precipitate of barium phosphate. Through the use of filtration, the precipitate was removed from the mixture completely. The filtered liquid was transferred into multiple test tubes, each test tube had either barium chloride or sodium phosphate added into the liquid. The chemical that caused a precipitant to form was determined to be the limiting reactant. The filter containing the barium phosphate that was filtered from the liquid was then dried and later massed. Using

Mass of BaCl₂∙2H₂O for trial 1
(m_(BaCl^2∙2H^2 O))=( mol BaCl_2∙2H_2 O)|(244.3 g BaCl_2∙2H_2 O )/(1 mol BaCl_2∙2H_2 O)
(m_(BaCl₂∙2H₂O))= 5.187×〖10〗^(-4) mol BaCl_2∙2H_2 O|(244.3 g BaCl_2∙2H_2 O )/(1 mol BaCl_2∙2H_2 O)
(m_(BaCl₂∙2H₂O))=0.1267g BaCl₂∙2H₂O

The percent composition of the limiting reactant (% comp) was calculated by dividing the mass of the limiting reactant (m_(BaCl₂∙2H₂O)) by the mass of the original sample (m_s) and multiplying the product by 100 Percent composition of BaCl₂∙2H₂O for trial 1
(% comp)= ((m_(BaCl₂∙2H₂O)) )/((m_s) )×100
(% comp)= ((0.1267g BaCl₂∙2H₂O ) )/((1.0490g) )×100
(% comp)=12.08 % BaCl₂∙2H₂O

Identification of Limiting Reactant and Percent Composition
The unknown sample used in this experiment was # 123. The limiting reactant was determined to be barium chloride dihydrate making sodium phosphate the excess reactant. The average percent composition from trial 1 and trial 2 was found to be 12.68 % BaCl_2∙2H_2 O and 87.32 %