[orgo814]

"you are attempting to determine Km by measuring the reaction velocity at different substrate concentrations, but you do not realize that the substrate tends to precipitate under the experimental conditions you have chosen. How would this affect your measurement of Km?"

Answer: "The experimentally determined Km would be greater than the true Km because the actual substrate concentration is less than expected".

How is the Km greater than expected when the substrate concentration is less? I don't see how this makes sense. If the substrate concentration is less (and the Km is by definition a substrate concentration at Vmax/2) than how is it greater?

Thanks for any help