Hydroxide Ion (OH-): This is an ion consisting of oxygen and hydrogen joined by a covalent bond, carrying a negative electric charge. It's produced by bases in aqueous solutions.
Alkalinity: This refers to the capacity of water to resist changes in pH that would make it more acidic. It's related to the presence of compounds such as bases in the solution.
pH Scale:A logarithmic scale used to specify the acidity or basicity/alkalinity of an aqueous solution.