posted by Jayne .
Mg(s) + 2HCl(aq) → MgCl2(aq) + H2(g)
If 2.00 g of Mg reacts completely with 50.0 mL of HCl solution, what is the molarity of the HCl solution?
One needs twice the number of moles of HCl as Mg.
how many moles of Mg is there in 2g?
moles of HCL=twiceMolesMg=.050*Molarity
solve for molarity