Respuesta :

75mL=0.075L

Molarity=moles/Liters
Moles=0.075(3.50)
=0.2625

Since the number of moles never changes,
we know there are 0.2625moles (or 0.26) in the 12M HCl.
0.2625/12=0.021875L

(0.022L)