Question

calculate the pH of a solution prepared by dissolving 10.0 g of Tris hydroxymethyl aminomethane (trisbase) plus 10.0g of this hydrochloride in 0.250 l of water.

Answer 1

Molecular wt. of Tris hydroxymethyl aminomethane = 121.135gm eq.

Molecular wt. of hydrochloridee = 36.5gm.eq.

solution is prepared by dissolving 10.0 g of Tris hydroxymethyl aminomethane (trisbase) plus 10.0g of this hydrochloride in 0.250 l of water.

so,

in the solution 0.33M Tris hydroxymethyl aminomethane (trisbase) and 1.10M hydrochloride is present in 0.250 l of water.

conc. of any species can be calculated as follow

wt. given/mol.wt.=no. of moles

then, no. of moles / amount of solvent used = conc. in solution

net hydrochloride left is 0.77M.

then P^H= -log (0.77)

=0.1135