5 Draw the equation for the reaction happening when you add

5. Draw the equation for the reaction happening when you add concentrated NaOH in #5. What is happening to the H+ concentration of the solution?

Solution

A[H] + NaOH = NaA + H₂O

NaOH is a strong base and gives OH^- ions (hydroxide ions) in the solution when reacted with an acid. The hydroxide ion is combined to H⁺ ions (protons) of acid [AH] to make water molecules. This is required step to form a salt or compound. One mole of protons when react with one mole of hydroxide ions, form one mole of water. So water molecules always have equal concentration (in terms of moles) in respective of any of both ions are in less or high concentration in the solution. Free hydroxide ions concentration depends upon concentration of protons. If OH^- ions are more than H⁺ ions then there no H⁺ ions will remain in the solution.