1-19 continued (g)CH3-G=CH2 Lewis bas nucleophile Lewis acid- electrophile 1-20 w{g8- 9一-莒= (c)The last resonance form of SO,has no equivalent form in O;Sulfur,a third row element,can have more 1-21 (a)CARBON!(the best element)(b)oxygen (c)phosphorus (d)chlorine 1-22 valence e- .123415678 He(2e- Be B N 0 D Br 1-23 (a)ionic only (b)covalent (H-O)and ionic (Nat OH) (c)covalent (H-Cand C-Li).but the C-Li bond is strongly polarized (d)covalent only (e)covalent (H-C and C-O)and ionic (Nat -OCH3) (f)covalent (H-C and C=O and C-O)and ionic (HCO,-Na+) (g)covalent only 1-24 斌、 、 (a) (b) C C 道年年 CANNOT EXIST NCls violates the octet nle:nitrogen n have no more than eight elec s (or four atoms)around it d orbitals in bonding,so PCls is a stable,isolable compound. 1-25 Your Lewis structures may look different from these.As long as the atoms are connected in the H HH H-N-N-H (b)H-N=N-H ()H-( ④I (a) Ha9 HH HHH 13 Copyright013 Pearson Education,Inc