TSR DECISIONS DROP IN Q and A NOW OPEN - GET FREE ADVICE HERE >>

Higher chem help!

Excitedcow

For my chemistry assignment, how does a colour change help me be able to measure the reaction rate?

Reply 1

TypicalNerd

Original post by Excitedcow

For my chemistry assignment, how does a colour change help me be able to measure the reaction rate?

Generally colour change is monitored using a technique called colourimetry. The Beer-Lambert law states that the absorbance of the relevant wavelength of visible light is proportional to the concentration of the coloured compound in solution. As such, either a spectrophotometer or colourimeter can be used to track how much of this particular wavelength of light is absorbed and therefore how the concentration of a coloured product or reactant varies as the reaction progresses.

(edited 1 month ago)

Reply 2

thisisbatcountry

This was posted a while ago hopefully it's not too late sorry. a colour change signifies the end of a chemical reaction, so you can time how long it takes a reaction to change colour, and this will be the time taken to react. From this you can calculate the relative reaction rate.