Which image best represents a solution of distilled water at pH = 7? A cylinder contains many pale blue balls and 3 purple balls. A box has a pale blue ball with the label H + and a purple ball with the label O H negative. A cylinder contains about equal numbers of pale blue balls and purple balls. A box has a pale blue ball with the label H + and a purple ball with the label O H negative. A cylinder contains 3 pale blue balls and many purple balls. A box has a pale blue ball with the label H + and a purple ball with the label O H negative.