What is the molar concentration of hydronium ion in pure water at 25 degrees C? Chemistry Solutions Molarity 1 Answer anor277 Jan 2, 2017 #10^-7# #mol*L^-1#. Explanation: #K_"water"# #=# #[H_3O^+]xx[HO^-]=10^-14# at #298*K# At temperatures above #298*K#, how do you think this equilibrium would evolve? Answer link Related questions what is the molarity of 20.0 ml of a KCl solution that reacts completely with 30.0 ml of a 0.400... How can molarity and osmolarity be calculated from mass per unit volume? How can molarity be used as a conversion factor? How high can molarity be? How does molarity change with temperature? How do you find molarity of a solution? What is the molarity of 10 NaOH? What is the molarity of 3 hydrogen peroxide? What is the molarity of a solution that contains 3.2 mol of solute in 0.98 L of solution? What is molarity? See all questions in Molarity Impact of this question 18274 views around the world You can reuse this answer Creative Commons License