4 CHAPTER 1 Structure and Properties of Organic Compounds H/'s project toward viewer Hs project away Irom view H H Figure 1.3 Problem1.5 Write Lewis structures for(a)hydrazine,N,H(b)phosgene.COCl:and(c)nitrous acid,HNO In general,first bond the multicovalent atoms to each other and then,to achieve their normal covalences bond them to the univalent atoms (H,Cl,Br.Iand F).If the number of univalent atoms is insufficient for this structure sh (a)N needs three covalent bonds,and H needs one.Each N is bonded to the other N and to two H's. (b)Cis bonded to Oand to each Cl.To satisfy the tetravalence of C and the divalence of a double bond is placed between C and O. the N. and the other O.(Convince yourself that bonding the Hto the N would not lead structure.) H-i-i-6: Problem 1.5 Write Lewis structures for (a) hydrazine, N2 H4 ; (b) phosgene, COCl2 ; and (c) nitrous acid, HNO2 . In general, first bond the multicovalent atoms to each other and then, to achieve their normal covalences, bond them to the univalent atoms (H, Cl, Br, I, and F). If the number of univalent atoms is insufficient for this purpose, use multiple bonds or form rings. In their bonded state, the second-period elements (C, N, O, and F) should have eight (an octet) electrons but not more. Furthermore, the number of electrons shown in the Lewis structure should equal the sum of all the valence electrons of the individual atoms in the molecule. Each bond represents a shared pair of electrons. (a) N needs three covalent bonds, and H needs one. Each N is bonded to the other N and to two H’s. 4 CHAPTER 1 Structure and Properties of Organic Compounds Figure 1.2 Figure 1.3 (b) C is bonded to O and to each Cl. To satisfy the tetravalence of C and the divalence of O, a double bond is placed between C and O. (c) The atom with the higher covalence, in this case the N, is usually the more central atom. Therefore, each O is bonded to the N. The H is bonded to one of the O atoms, and a double bond is placed between the N and the other O. (Convince yourself that bonding the H to the N would not lead to a viable structure.)