[f77126]

So I measured the velocity of the reaction with spectrophotometer which gives unit of "absorbance unit/min". What is the desired unit of the velocity in mechaelis-menten equation? Also how do I convert to that unit from absorbance unit/min. Thanks!

[Borek]

Absorbance is in simple relation to concentration.

Are you from one of those schools that don't teach Beer-Lambert law? Plenty of those lately.

[Yggdrasil]

Note that even when using abs/min as your units for the Michaelis Menten equation, you can still get an accurate value of Km in the appropriate units.  The Vmax you obtain, however, will be in units of abs/min and require conversion to concentration/min using Beer's law as Borek has said.

[f77126]

Well my instructor just said to divide the rate in absorbance unit by extinction coefficient but didn't say anything about beer-law, so I was just making sure. Thanks for the response

[Borek]

divide the rate in absorbance unit by extinction coefficient but didn't say anything about beer-law

This is a direct application of the Beer-Lambert law, so basically what you are saying is "instructor said to calculate square root of sum of squares of sides about the right angle, but didn't say anything about Pythagorean theorem"