This is an excellent opening activity to the calculations for determining molarity and concentration of a solution. Students do a micro-titration of six concentrations of NaOH with 1.0 M HCl and phenolphthalein as an indicator. They create a graph and determine the slope of the line, then write an equation for determining the molarity using the technique. They then determine the molarity of an unknown solution of NaOH.
This is a microchemistry lab, so one you set it up, all you have to do is top up the solutions and you are ready to go, year after year.
Inquiry labs are an excellent way to get students to think about how we know what we know in chemistry and I find them to be far more successful in a topic by using them. In addition, the change from hot pink for phenolphthalein to colorless is a breathtaking moment for students. (Mine actually snap chatted it this year)
• Hands on experience
• Cooperative Learning
• Teacher instructions and set up
• Reinforcement of difficult concepts
• Student handouts with a key
chemistry, experiment, lab, laboratory, STEM, titration, acid, base, molarity, molality, normality, concentration, mole, moles, liters