If 525 mL of 0.80 M HCl solution is neutralized with 315 mL of Sr(OH)2 solution what is the molarity of the Sr(OH)2? __ HCl + __ Sr(OH)2  __ SrCl2 + __ H2O

1 Answer

The molarity of Sr(OH)_2 is "0.67 M"

Explanation:

Acids and bases neutralize each other. Strontium hydroxide will neutralize hydrochloric acid to produce a salt and water. The reaction will be

Sr(OH)_2 + 2HCl -> SrCl_2 + 2H_2O

  • the volume of strontium hydroxide is "315 mL"
  • the volume of hydrochloric acid is "525 mL"
  • the molarity of hydrochloric acid is "0.80 M"

Steps:

The number of moles of HCl consumed in the process

"Moles" = "Concentration" xx "Volume"

is equal to

= "0.8 moles"/"1000 ml" * "525ml" = "420 millimoles"

Here

"milli" = 1/1000

For every mole of HCl, half a mole of strontium hydroxide is neutralized as observed from the stoichiometry (or balanced equation).

Therefore, the number of moles of strontium hydroxide is equal to

"420 millimoles"/2 = "210 millimoles"

Therefore, the concentration of strontium hydroxide will be

"210 millimoles" / "315 ml" = "0.66667 millimoles/mL" = "0.67 moles/L" = "0.67 M"