Include all the quantities required, concisely describe how you would make 50mL of a 0.5% (w/v) solution of BSA (molecular weight: 66 400) using water as a diluent

Question

Include all the quantities required, concisely describe how you would make 50mL of a 0.5% (w/v) solution of BSA (molecular weight: 66 400) using water as a diluent

Answer 1

The molecular weight is not needed to solve this problem. It would only be useful if one wanted to know the molarity of the final solution.

A 0.5% (w/v) means there is 0.5 g in 100 mls of solution. That is the definition of a 0.5% (w/v) solution.

So, to make 50 mls (one half of the 100 mls defined) you would need 0.15 g in 50 ml of solution.

To make the solution, one would weigh out 0.25 g (250 mg) of BSA and in a 50 ml volumetric flask, dissolve the powder in water and bring to the 50 ml mark. This yields 50 ml of a 0.5% (w/v) solution of BSA.