We will need 0.5L extraction buffer with 25 mM HEPES, 1 mM EDTA, and 1 mM DTT. Please calculate how many grams of each solute are needed. (HEPES 238.3; EDTA 292.2; DTT 154.2)
How many moles each do you need?
That's mols = M x L = ?
EDTA = 0.001 x 0.5 = ?
etc.
Then grams = mols x molar mass = ?
The others are done the same way.
Thank you!
To calculate the mass of each solute needed, we can use the formula:
Mass (g) = Molarity (mol/L) x Volume (L) x Molecular Weight (g/mol)
1. For HEPES:
Given:
Molarity of HEPES = 25 mM
Volume of extraction buffer = 0.5 L
Molecular Weight (MW) of HEPES = 238.3 g/mol
Using the formula mentioned above:
Mass of HEPES (g) = 25 mM x 0.5 L x 238.3 g/mol
Calculating the above expression:
Mass of HEPES = 5.9575 g
2. For EDTA:
Given:
Molarity of EDTA = 1 mM
Volume of extraction buffer = 0.5 L
Molecular Weight (MW) of EDTA = 292.2 g/mol
Using the formula mentioned above:
Mass of EDTA (g) = 1 mM x 0.5 L x 292.2 g/mol
Calculating the above expression:
Mass of EDTA = 0.1461 g
3. For DTT:
Given:
Molarity of DTT = 1 mM
Volume of extraction buffer = 0.5 L
Molecular Weight (MW) of DTT = 154.2 g/mol
Using the formula mentioned above:
Mass of DTT (g) = 1 mM x 0.5 L x 154.2 g/mol
Calculating the above expression:
Mass of DTT = 0.0771 g
Therefore, you will need approximately:
- 5.9575 grams of HEPES
- 0.1461 grams of EDTA
- 0.0771 grams of DTT for the extraction buffer.