What is the pH of a solution with a hydroxyl ion [OH?] concentration of 10?¹² M? Biology What is the pH of a solution with a hydroxyl ion [OH?] concentration of 10?¹² M? A) pH 2 B) pH 4 C) pH 10 D) pH 12 E) pH 14 Answer: A Learn More : Share this Share on FacebookTweet on TwitterPlus on Google+