What weight in grams would you need of Tris....

Question

What weight in grams would you need of Tris (MWT 121 g/mol) to prepare 250 ml of a 10% w/v solution?

Answer 1

10% w/v solution means 10 g of solute per 100 mls of solution.

To prepare 250 mls, you will need 2.5 x that amount, i.e. 10g/100 ml x 250 ml = 25 grams

Note:  the molar mass of Tris does not enter into these calculations because they do not ask for molarity.