Respuesta :

as i am reading the problem, i notice they give two concentrations (M), a volume and asking for the other volume; this should be a hint that we need to use the dilution formula---> M1V1 = M2V2

M1= 2.55 M
V1= ?
M2= 0.75 M
V2= 125 mL

now, we plug in the values into the formula

(2.55 x V1) = (0.75 x 125)

V1= 36.8 mL