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Structure 1.4.5—The molar concentration is determined by the amount of solute and the volume of solution.


Here are experiments our science specialists have selected to support this IB* topic.

Messed Up Makeup (Drop Counter)

Experiment #9A from Forensic Chemistry Experiments

  • Use a pH sensor to monitor changes in pH as sodium hydroxide solution of unknown concentration is titrated with hydrochloric acid solution of known concentration.
  • Plot a graph of pH vs. volume of sodium hydroxide solution added.
  • Use the graph to determine the volume of hydrochloric acid added to reach the equivalence point of the titration.
  • Use the results to calculate the concentration of the sodium hydroxide solution titrated.
  • Use the results to calculate the mass of sodium hydroxide added to the makeup remover bottle.

Educational Standard
International Baccalaureate (IB) 2025
Organizing concepts
Structure 1. Models of the particulate nature of matter
Structure 1.4—Counting particles by mass: The mole
Standard level and higher level

* The IB Diploma Program is an official program of the International Baccalaureate Organization (IBO) which authorizes schools to offer it. The material available here has been developed independently of the IBO and is not endorsed by it.