The figure shows two nitrophenols, I and II. Read five statements on their hydrogen bonds. (i) In I, the hydrogen bond forms within one molecule. (ii) In II, hydrogen bonds link the OH group of one molecule to the nitro group of another. (iii) The hydrogen bond in I closes a ring of six atoms, counting the hydrogen. (iv) Molecules of I hold one another more strongly than molecules of II do. (v) A hydrogen bond is stronger than an O-H covalent bond. How many of these statements are correct?

Fig. 1: Two skeletal structures of benzene rings, each carrying an OH group and a nitro group. The nitro group is drawn as a nitrogen with a plus charge, a double bonded oxygen and a single bonded oxygen with a minus charge. In structure I the OH group and the nitro group are on neighbouring carbon atoms of the ring. In structure II they are on opposite carbon atoms of the ring, across from each other. No hydrogen bonds are drawn.