NaOH Is Added to Sea Water Containing 0

Multiple Choice

NaOH is added to sea water containing 0.050 moles per liter of Mg²⁺ ion until the pH reaches 12.0. A certain quantity of Mg(OH) ₂ precipitates. How many parts per billion of magnesium are left behind in the solution? The K_sp of Mg(OH) ₂ is 7.1 × 10^-12.Hint: Find [Mg^{2+], then convert to ppb.}

A) 1.2 ppb
B) 12 ppb
C) 0.17 ppb
D) 1.7 ppb
E) 173 ppb