Hydrolysis of an Ester

Here, we show the laboratory preparation for 10 students working in pairs, with some excess. Please adjust quantities as needed.

• Before you get started, put on a lab coat, safety glasses, and nitrile gloves. Ensure that the lab is equipped with enough lab coats, splash goggles, and gloves for all of the students.
• Prepare 1 L of 3 M NaOH. Measure 120 g of NaOH pellets, and transfer the pellets to a 1-L volumetric flask. Add deionized water to the 1-L line. Place a stir bar in the flask and mix the solution until the pellets are fully dissolved.
• Once the solution is homogeneous, transfer the solution to a glass bottle, cap it, and label it. Place the bottle in a central hood so that students have access to it.
• Prepare 1 L of 1 M CaCl₂ solution. Weigh 110.98 g of CaCl₂, and transfer it to a 1-L volumetric flask. Fill the flask to the marked line with deionized water, add a stir bar, and mix the solution on a stir plate until the CaCl₂ is fully dissolved.
• Once the solution is homogeneous, transfer it to a clean glass bottle, cap it, and label it. Store the solution in a central hood.
• Prepare at least 1 L of 3 M HCl, which will be used to neutralize any excess sodium hydroxide at the end of the experiment.
• Obtain 5 silicone soap molds and leave them in a common area. Obtain at least five different fragrance oils and five powder soap dyes in a variety of colors, and set them near the molds.
• Place a container of commercial liquid soap in a common area. Set coconut oil next to the balance making sure there are clean spatulas and weighing boats.
• Set out the following glassware and equipment at each student lab station (we suggest that students work in pairs):

  1    Stir bar

  1    Hotplate

  1    Package of pH paper

  1    pH meter

  1    250-mL plastic squeeze bottle of DI water

  2    50-mL volumetric flasks

  2    100-mL glass graduated cylinders

  6    50-mL glass graduated cylinders

  1    50-mL beaker

  2    400-mL beaker

  2    Glass vials

  1    Glass stirring rod

  1    Small spoon

  1    Small spatula