PROBLEM \(\PageIndex{1}\) Write Lewis structures for the following: (please note, none of the solutions are using the expanded octet rule or formal charges) H 2 HBr PCl 3 SF 2 H 2 CCH 2 HNNH H 2 CNH NO – N 2 CO CN – Answer a Answer b Answer c Answer d Answer e Answer f Answer g Answer h Answer i Answer j Answer k PROBLEM \(\PageIndex{2}\) Write Lewis structures for the following: (please note, none of the solutions are using the expanded octet rule or formal charges) O 2 H 2 CO ClNO SiCl 4 H 3 O + \(\ce{NH4+}\) \(\ce{BF4-}\) HCCH ClCN \(\ce{C2^2+}\) Answer a Answer b Answer c Answer d Answer e Answer f Answer g Answer h Answer i Answer j PROBLEM \(\PageIndex{3}\) Write Lewis structures for: (please note, none of the solutions are using the expanded octet rule or formal charges) a. \(\ce{PO4^3-}\) c. \(\ce{SO3^2-}\) d. HONO Answer a Answer b Answer c Click here to see a video of the solution PROBLEM \(\PageIndex{4}\) Methanol, H 3 COH, is used as the fuel in some race cars. Ethanol, C 2 H 5 OH, is used extensively as motor fuel in Brazil. Both methanol and ethanol produce CO 2 and H 2 O when they burn. Write the chemical equations for these combustion reactions using Lewis structures instead of chemical formulas. Answer PROBLEM \(\PageIndex{5}\) Many planets in our solar system contain organic chemicals including methane (CH 4 ) and traces of ethylene (C 2 H 4 ), ethane (C 2 H 6 ), propyne (H 3 CCCH), and diacetylene (HCCCCH). Write the Lewis structures for each of these molecules. (diacetylene may be a little tricky!) Answer Click here to see a video of the solution PROBLEM \(\PageIndex{6}\) Carbon tetrachloride was formerly used in fire extinguishers for electrical fires. It is no longer used for this purpose because of the formation of the toxic gas phosgene, Cl 2 CO. Write the Lewis structures for carbon tetrachloride and phosgene. Answer PROBLEM \(\PageIndex{7}\) The arrangement of atoms in several biologically important molecules is given here. Complete the Lewis structures of these molecules by adding multiple bonds and lone pairs. Do not add any more atoms. a. the amino acid serine: b. urea: c. pyruvic acid: d. uracil: e. carbonic acid: Answer a Answer b Answer c Answer d Answer e PROBLEM \(\PageIndex{8}\) How are single, double, and triple bonds similar? How do they differ? Answer Each bond includes a sharing of electrons between atoms. Two electrons are shared in a single bond; four electrons are shared in a double bond; and six electrons are shared in a triple bond. Contributors Paul Flowers (University of North Carolina - Pembroke), Klaus Theopold (University of Delaware) and Richard Langley (Stephen F. Austin State University) with contributing authors. Textbook content produced by OpenStax College is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/85abf193-2bd...a7ac8df6@9.110 ). Adelaide Clark, Oregon Institute of Technology Feedback Think one of the answers above is wrong? Let us know here .