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10 mL 5 M calcium hydroxide is required to titrate 50 mL hydrochloric acid. Which of the following gives the initial concentration of the acid?
So I though that you find the moles of Ca(OH)2 and then that equals the moles of HCL. Then divide the moles of HCL by the volume of HCL.
(1 x 10^-2 ) (5 x 10^-1) = 5 x 10 ^-3 moles / 5 x 10 ^-2 L HCL = 0.1M
But the answer is apparently 1/5 M. I'm confused, does it have to do with the fact that its a strong acid being tit-rated and somehow half the moles of the base are needed.
EDIT: I get it its a 2:1 molar ratio of HCL to ca(OH)2
So I though that you find the moles of Ca(OH)2 and then that equals the moles of HCL. Then divide the moles of HCL by the volume of HCL.
(1 x 10^-2 ) (5 x 10^-1) = 5 x 10 ^-3 moles / 5 x 10 ^-2 L HCL = 0.1M
But the answer is apparently 1/5 M. I'm confused, does it have to do with the fact that its a strong acid being tit-rated and somehow half the moles of the base are needed.
EDIT: I get it its a 2:1 molar ratio of HCL to ca(OH)2
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