Alka-Seltzer Lab Essay

405 Words2 Pages
Investigating the Chemical Composition of Alka Selzter Problem: How much sodium bicarbonate is in a tablet of Alka Seltzer? Purpose: To discover the amount of sodium bicarbonate, in grams, in a one tablet of Alka Seltzer. Materials: one Alka Seltzer tablet 50 mL of vinegar post-it note Triple beam balance beaker Procedure: 1) Put the post-it on the triple beam balance and zero the balance. 2) Measure the masses of the alka-seltzer tablet, and the beaker + vinegar. Record them. 3) Measure the temperature of the vinegar in the beaker using a thermometer. Record it. 4) Drop the tablet of alka-seltzer into the beaker of vinegar. Record ur observations. 5) Wait until the reaction has completely finished. Then measure the mass of the beaker and its contents. 6) Subtract the mass of the beaker and its contents from the initial total mass of the tablet, beaker, and vinegar. This is the mass of the carbon dioxide. CALCULATING AMT. OF SODIUM BICARBONATE 7) Calculate the number of moles of carbon dioxide in the reaction. 8) The number of moles of carbon dioxide is also the number of moles of H2CO3 in the reaction H2CO3 H2O + CO2. 9) The number of moles of H2CO3 in the reaction NaHCO3 + C2H4O2 NaC2H3O2 + H2CO3 is also the number of moles of NaHCO3. 10) Calculate the number of grams of sodium bicarbonate by multiplying the number of moles of sodium bicarbonate by its molar mass. OBSERVATIONS BEFORE REACTION Total Mass: 165.93 g Total Mass: 165.93 g Mass: Alka Seltzer Tablet: 3.82 g Beaker + Vinegar: 162.11 g Temperature: 20.9 °C DURING REACTION Observations: Alka Seltzer is fizzing and dissolving into the vinegar Gas is being released as bubbles form; it’s carbon dioxide Looks like a nice glass of frothy beer AFTER REACTION Observations: