Spectrophotometry Experiment

An interesting challenge in science is measuring things that can't be measured directly.

Direct measurements are pretty straight forward.  If you want to know the mass of a pencil, you simply use a balance to measure the pencil's mass.  Sometime there are things that we want to measure which can't be measured directly.  Luckily we can use indirect measurements.  This is when we measure one thing to determine a different measurement.

This video shows an experiment using a spectrophotometer to measure the amount of light which is absorbed by a solution of iron (III) chloride.  The data can be used to create a standard curve which will be used to calculate the concentration of the solution of iron(III) chloride.  The concentration of the iron (III) chloride can't be measured directly by the spectrophotometer, but it can be determined as an indirect measurement by analyzing the absorption data.


I hope this was helpful!

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