 This method is often used to determine the boron content in the water of the primary circuit of light-water reactor, in which boric acid is added as a neutron moderator to control the reactivity of the core.At neutral pH boric acid undergoes condensation reactions to form polymeric oxyanions.Well-known polyborate anions include the triborate(1−), tetraborate(2−) and pentaborate(1−) anions.