What is the molarity of a strontium hydroxide solution if 56.4 mL is needed to neutralize 35.0 mL of 0.85 M perchloric acid?

Question

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Answer 1

Sr(OH)₂ + 2HClO₄ ... balanced equation

moles HClO₄ neutralized = 0.0350 L x 0.85 mol/L = 0.02975 moles

moles Sr(OH)₂ needed = 0.02975 moles HClO₄ x 1 mole Sr(OH)₂/2mole HClO₄ = 0.0149 moles Sr(OH)₂

molarity of Sr(OH)₂ = 0.0149 moles/0.0564 L = 0.26 M (to 2 sig. figs.)