The volume of the 18M HCl needed to make the solution will be 2.5 mL.
Dilution
According to the dilution principle, the number of moles of solutes in a solution before and after dilution must remain the same.
Since, mole = molarity x volume
Thus, molarity x volume before dilution = molarity x volume after dilution.
Mathematically, the equation is written as: m1v1 = m2v2
In this case, m1 = 18 M, m2 = 1.5 M, and v2 = 30 mL.
What we are looking for is v1, the amount of the stock HCl needed for dilution.
v1 = m2v2/m1 = 1.5 x 30/18 = 2.5 mL.
Thus, 2.5 mL of the stock HCl would be needed.
More on dilution can be found here: https://brainly.com/question/21323871
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