Hydroxyapatite, Which Is a Component of Tooth Enamel, Is Very

Multiple Choice

Hydroxyapatite, which is a component of tooth enamel, is very insoluble in water. For the following reaction, K_sp  2.3  10^59. What is the molar concentration of Ca₅(PO₄) ₃^ when the pH of the mouth is 4.0?

A) 2.3  10^49 M
B) 2.3  10^59 M
C) 2.3  10^55 M
D) 2.3  10^63 M
E) 0, teeth don't dissolve!