Which statements explain the shape of the titration curve observed in lab?
I. Initially, the conductivity is zero since the reaction has not begun.
II. During the reaction, the conductivity decreases due to the increase of Ba+2 and OH– ions.
III. At the equivalent point, the conductivity is nearly zero since all the Ba+2 and OH– ions have reacted to produce nonelectrolyte products.
IV. After the endpoint, the conductivity increases due to the excess titrant.