Exhibit 15-3 Ephedrine (C₁₀H₁₅ON), a Central Nervous System Stimulant, Is

Exhibit 15-3 Ephedrine (C₁₀H₁₅ON) , a central nervous system stimulant, is used in nasal sprays as a decongestant. This compound is a weak organic base :
C₁₀H₁₅ON (aq) + H₂ O HC₁₀H₁₅ON + (aq) + OH - (aq) Consider a 0.035 M
Solution of ephedrine that has a pH of 11.33 to answer the following problem(s) .
-Refer to Exhibit 15-3. What is the equilibrium concentration of ephedrine, C₁₀H₁₅ON eq , in this 0.035 M solution?

A) 4.7×10 ^{- 12} M
B) 2.1×10 ^{- 3} M
C) 3.3×10 ^{- 2} M
D) 3.7×10 ^{- 2} M
E) 4.5×10 ^{- 2} M