In a reaction you use 400 ul of 12mM B-galactosidase. Add 2.3 ml of buffer and 0.3ml of ONPG to a cuvette. what is the final concentration of the cuvette? Answer below to one decimal place.

Also...A stock solution of ONPG has a concentration of 25 mM. Add 2.8 mL of buffer, 0.3

mL of enzyme and 0.9 mL of ONPG to a cuvette. What is the final concentration of
ONPG in the cuvette? Answer below to one decimal place

you are diluting it (.4+2.3+.3)/.4=7.5 times

final concentration=12.5/7.5 mM B-galactosidase

second diluting it (2.8+.3+.9)/.9=4.4times
concentration=25/4.4=5.7 mM

To find the final concentration of the cuvette, we need to calculate the total volume of the cuvette first, and then determine the amount of B-galactosidase that is contained within that volume.

First, let's calculate the total volume of the cuvette:

Total volume = Volume of buffer + Volume of ONPG
= 2.3 ml + 0.3 ml
= 2.6 ml

Now, we can determine the amount of B-galactosidase in the total volume of the cuvette. The initial volume of B-galactosidase is given as 400 ul, which is equal to 0.4 ml.

To calculate the final concentration, we use the formula:

Final concentration (in mM) = (Amount of B-galactosidase (in moles) / Total volume (in liters)) * 1000

First, convert the volume from milliliters to liters:

Total volume (in liters) = 2.6 ml / 1000
= 0.0026 liters

Now, we can calculate the amount of B-galactosidase in moles:

Amount of B-galactosidase (in moles) = (0.12 M) * (0.4 ml / 1000)
= 0.12 * 0.4 / 1000
= 0.048 mmol

Finally, to calculate the final concentration:

Final concentration (in mM) = (0.048 mmol / 0.0026 L) * 1000
= 18.5 mM

Therefore, the final concentration of the cuvette is 18.5 mM.