Answer: 0.4 moles
Explanation:
Given that:
Amount of moles of HCI = Z (let unknown value be Z)
Volume of HCl = 500.0 mL
Convert 500.0 mL to liters
If 1000ml = 1L
500.0 mL = (500.0 mL/1000mL) = 0.5L
Molarity of HCl solution = 0.200M
Recall that molarity of a solution is obtained by dividing the amount of moles by volume in liters
i.e Molarity = Amount in moles/volume
0.200M = Z x 0.5L
Z = 0.200M / 0.5L
Z = 0.4 moles
Thus, 0.4 moles of HCl is needed to make the solution