How do I calculate 50ml of a 50mM sodium momophosphate buffer solution
To calculate the amount of sodium monophosphate required for a 50mM buffer solution, you will need to find the molar mass of sodium monophosphate and use it to determine the amount of solute needed.
Here's a step-by-step guide:
1. Find the molar mass of sodium monophosphate (NaH2PO4). The molar mass can be calculated by adding the atomic masses of each element in the compound.
- Molar mass of Na = 22.99 g/mol (atomic mass of sodium)
- Molar mass of H2PO4 = (1.01 x 2) + 31.00 + (16.00 x 4) = 97.01 g/mol (atomic mass of hydrogen, phosphorous, and oxygen)
Add the individual molar masses together:
- NaH2PO4 = 22.99 + 97.01 = 120.00 g/mol
2. Calculate the amount of sodium monophosphate needed for a 50mM solution.
The term "50mM" represents 50 millimoles per liter, which means there would be 50 millimoles (mmol) of sodium monophosphate in one liter of solution.
To calculate the number of moles, we can convert millimoles (mmol) to moles (mol):
- 50 mmol = 50 x 10^-3 mol
3. Determine the amount of sodium monophosphate needed for 50 millimoles.
Using the molar mass of sodium monophosphate, we can calculate the mass needed:
- Mass (g) = moles x molar mass
Substituting the values:
- Mass (g) = 50 x 10^-3 mol x 120.00 g/mol = 6 g
4. Finally, convert the mass to volume.
Given that you want to prepare a 50ml solution of 50mM sodium monophosphate buffer, you need 6 grams of sodium monophosphate.
Keep in mind that sodium monophosphate may not be fully soluble in water, so you might need to dissolve it in less than 50ml and then make up the volume to 50ml using water or buffer solution.
This calculation assumes you are starting with dry sodium monophosphate and that the final solution will be made up to the desired volume with water or buffer solution.