Hydroxyapatite, Which Is a Component of Tooth Enamel, Is Very $\rightleftarrows$

question 74

Short Answer

Hydroxyapatite, which is a component of tooth enamel, is very insoluble in water. For the following reaction, K_sp = 2.3 *10^-59.
Ca₅ (PO₄)₃(OH)(s) $\rightleftarrows$ Ca₅ (PO₄)₃⁺(aq) + OH^-(aq)
What is the molar concentration of Ca₅(PO₄)₃⁺ when the pH of the mouth is 4.0?

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Definitions:

Optic Nerve

The nerve that transmits visual information from the retina to the brain.

Choroid Layer

A layer of the eye containing blood vessels and pigment cells, located between the retina and the sclera, primarily responsible for providing oxygen and nourishment to the outer layers of the retina.

Sclera

White, fibrous, outer layer of the eyeball.

Sensory Adaptation

Change in the sensitivity of a receptor that usually makes the receptor less sensitive to its stimulus.