[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"doc-seo-348167-105":3,"detail-sidebar-cat-0-en-105":81,"doc-detail-348167-en":131},{"code":4,"msg":5,"data":6},0,"ok",{"site_id":7,"language":8,"slug":9,"title":10,"keywords":11,"description":12,"schema_data":13,"social_meta":74,"head_meta":76,"extra_data":78,"updated_unix":80},105,"en","chem-322-midterm-2-answer-key","CHEM 322 - Midterm 2 - Answer Key","","CHEM 322 Midterm 2 (Spring 2014) Watson and Hietbrink exam answer key content focuses on interpreting NMR, IR, and mass spectrometry data and predicting product outcomes for organic chemistry questions. The exam covers estimating 13C signal counts, predicting 1H NMR splitting and integrations, matching IR spectra to compounds, explaining key mass spectrum peaks for 2-butanone, and determining degrees of unsaturation, symmetry, and structure from combined spectral evidence. It also includes resonance structure drawing and reaction mechanism/product prediction tasks.",{"@graph":14,"@context":73},[15,34,56],{"@type":16,"itemListElement":17},"BreadcrumbList",[18,23,27,31],{"item":19,"name":20,"@type":21,"position":22},"https://docshare.wps.com","Home","ListItem",1,{"item":24,"name":25,"@type":21,"position":26},"https://docshare.wps.com/document/","Document",2,{"item":28,"name":29,"@type":21,"position":30},"https://docshare.wps.com/document/exam/","Exam",3,{"item":32,"name":10,"@type":21,"position":33},"https://docshare.wps.com/document/chem-322-midterm-2-answer-key/348167/",4,{"url":32,"name":10,"@type":35,"image":36,"author":41,"headline":10,"publisher":44,"fileFormat":47,"inLanguage":8,"description":12,"dateModified":48,"datePublished":49,"encodingFormat":47,"isAccessibleForFree":50,"interactionStatistic":51},"DigitalDocument",{"url":37,"@type":38,"width":39,"height":40},"https://docshare.wps.com/thumbnails/chem-322-midterm-2-answer-key/348167.png","ImageObject",300,407,{"name":42,"@type":43},"Patrick","Person",{"url":19,"name":45,"@type":46},"DocShare","Organization","application/pdf","2026-10-30","2026-09-22",true,{"@type":52,"interactionType":53,"userInteractionCount":55},"InteractionCounter",{"@type":54},"ViewAction",15,{"@type":57,"mainEntity":58},"FAQPage",[59,65,69],{"name":60,"@type":61,"acceptedAnswer":62},"How do you predict the number of signals in a 13C NMR spectrum?","Question",{"text":63,"@type":64},"Count chemically non-equivalent carbon environments in the molecule. Equivalent carbons (by symmetry) produce the same signal, reducing the total number of distinct 13C peaks.","Answer",{"name":66,"@type":61,"acceptedAnswer":67},"What does the IR signal at about 1740 cm–1 suggest?",{"text":68,"@type":64},"A strong absorption near 1740 cm–1 indicates the presence of a carbonyl group typical of esters or related carbonyl-containing functional groups.",{"name":70,"@type":61,"acceptedAnswer":71},"How can combined IR, 13C NMR, and 1H NMR shifts determine the structure of an unknown?",{"text":72,"@type":64},"Use IR to identify functional groups, use 13C NMR chemical shifts to locate specific carbon types (e.g., carbonyl vs alkene/alkane carbons), and use 1H NMR chemical shifts, integrations, and splitting patterns to assign hydrogen environments and connectivity. Together, these constraints allow the most consistent structure to be chosen.","https://schema.org",{"og:url":32,"og:type":75,"og:title":10,"og:site_name":45,"og:description":12},"article",{"robots":77,"canonical":32},"index,follow",{"doc_id":79,"site_id":7},348167,1790241629,{"code":4,"msg":82,"data":83},"success",[84,88,92,95,100,105,110,115,120,123,127],{"id":22,"doc_module":4,"doc_module_name":25,"category_name":85,"show_sort_weight":86,"slug":87},"Story & Novel",90,"story-novel",{"id":26,"doc_module":4,"doc_module_name":25,"category_name":89,"show_sort_weight":90,"slug":91},"Literature",80,"literature",{"id":33,"doc_module":4,"doc_module_name":25,"category_name":29,"show_sort_weight":93,"slug":94},70,"exam",{"id":96,"doc_module":4,"doc_module_name":25,"category_name":97,"show_sort_weight":98,"slug":99},5,"Comic",60,"comic",{"id":101,"doc_module":4,"doc_module_name":25,"category_name":102,"show_sort_weight":103,"slug":104},6,"Technology",50,"technology",{"id":106,"doc_module":4,"doc_module_name":25,"category_name":107,"show_sort_weight":108,"slug":109},7,"Healthcare",40,"healthcare",{"id":111,"doc_module":4,"doc_module_name":25,"category_name":112,"show_sort_weight":113,"slug":114},8,"Research & Report",30,"research-report",{"id":116,"doc_module":4,"doc_module_name":25,"category_name":117,"show_sort_weight":118,"slug":119},9,"Religion & Spirituality",20,"religion-spirituality",{"id":118,"doc_module":4,"doc_module_name":25,"category_name":121,"show_sort_weight":118,"slug":122},"World Cup","world-cup",{"id":124,"doc_module":4,"doc_module_name":25,"category_name":125,"show_sort_weight":124,"slug":126},10,"Lifestyle","lifestyle",{"id":128,"doc_module":4,"doc_module_name":25,"category_name":129,"show_sort_weight":96,"slug":130},19,"General","general",{"code":4,"msg":82,"data":132},{"doc_id":79,"user_id":133,"nickname":42,"user_avatar":134,"doc_module":4,"category_id":33,"category_name":29,"doc_title":10,"doc_description":12,"doc_content":135,"file_id":136,"file_url":137,"file_type":138,"file_size":139,"view_count":55,"is_deleted":4,"is_public":22,"is_downloadable":22,"audit_status":22,"page_count":140,"language":141,"language_code":8,"site_id":7,"html_lang":8,"table_of_contents":142,"faqs":143,"seo_title":144,"seo_description":12,"update_tm":145,"read_time":146,"preview_page_count":4},549758146520,"https://ap-avatar.wpscdn.com/avatar/80002397d8c0411e94?_k=1775819394049821470","Name:    \nCHEM 322. Midterm 2  \nSpring 2014  \nWatson, Hietbrink  \nPlease write your answers clearly in the boxes provided. If your answer is illegible or outside the box, it will not be graded. You may use the back of test pages for scratch work.  \nYou may use molecular models.  \nUse of calculators, cell phones, headphones, or any other electronic device during this exam is prohibited.  \nNo notes or books may be used during this exam. Tables of spectral data and a periodic table are provided at the end of this exam.  \nYou may raise your hand to ask a question if you are not sure what is being asked of you.  \nThere are -- pages in this exam. Please check that your test has -- pages before you begin. The last 2 pages are blank and may be used as scratch paper.  \nPlease circle your lecture:  \nHietbrink 8:00 AM class  \nHietbrink 11:15 AM class Watson class  \n\n| Question | Points |\n| --- | --- |\n| 1 |   /25 |\n| 2 |   /20 |\n| 3 |   /20 |\n| 4 |   /10 |\n| 5 |   /40 |\n| 6 |   /30 |\n| 7 |   /15 |\n| 8 |   /50 |\n| 9 |   /40 |\n| Total |   /250 |\n\nName:    \n1. (25 points) Predict how many signals you would see in the 13C spectrum of each of these molecules. Put your answer in the box below the molecule.  \nO  \nBrBr  \n2. (20 points) The 1H NMR of this compound should have four signals. Predict the splitting pattern (singlet, doublet, doublet of doublets, etc) you would see for each signal.  \nName:    \n3. (20 points) Below are the IR spectra for four of these eight compounds. Put the letter of the spectrum in the box below the appropriate compound.  \na) Spectra A and B refer to two of these four compounds.  \nb) Spectra A and B refer to two of these four compounds.  \nO  \nOH  \nNH2  \nName:    \n4. (10 points) Below is the mass spectrum of 2-butanone. In the boxes, explain the large peak at 43 and the small peak at 73.  \n43  \nO  \n73  \nName:    \n5. (40 points) Here are the IR, 13C NMR, and 1 H NMR spectra for an unknown with the formula C6 H 10O2. Answer questions on the next page.  \nC  \nName:    \n5 continued. (40 points) These questions all refer to the spectra on the previous page.  \na) How many degrees of unsaturation are in this compound?  \nb) Is there symmetry in this compound?  \nc) In the IR, what does the signal at about 1740 suggest?  \nd) In the 13C NMR, what does the chemical shift of the signal at about 105 suggest?  \ne) In the 1H NMR, what does the chemical shift of the signal at about 5.2 suggest?  \nf) In the 1H NMR, what does the integration of the signal at about 2.3 suggest?  \ng) In the 1H NMR, what does the splitting pattern of the signal at about 1.0 suggest?  \nh) What is the structure of this unknown?  \nName:    \n6. (30 points) Draw what you would expect to see in the 1H NMR of this compound. Your drawing should clearly show the number of signals, their approximate chemical shift (within 1 PPM) and the expected splitting pattern.  \nO  \nH  \nOCH3  \n11 10 9 8 7 6 5 4 3 2 1 0  \n7. (15 points) Draw the important resonance structures for this compound.  \nName:    \n8. (50 points) Predict the major organic product or products for the following reactions.  \nO  \nO2 N  \nCl Cl  \nNO2  \nH2 NNH2  \nKOH  \nheat  \nexcess CH3OH  \nH+  \nLi  \nliquid NH3  \nCH3O  \nexcess H2O  \nH+  \nName:    \n9. (40 points) Please draw a reasonable arrow-pushing mechanism for the following reaction.  \nName:    \nApproximate IR Absorption Frequencies  \n\n| Bond | Frequency (cm–1) | Intensity |\n| --- | --- | --- |\n| O–H (alcohol) | 3650–3200 | Strong, broad |\n| O–H (carboxylic acid) | 3300–2500 | Strong, very broad |\n| N–H | 3500–3300 | Medium, broad |\n| C–H | 3300–2700 | Medium |\n| C≡N | 2260–2220 | Medium |\n| C≡C | 2260–2100 | Medium to weak |\n| C=O | 1780–1650 | Strong |\n| C–O | 1250–1050 | Strong |\n\nApproximate 1H NMR Chemical Shifts  \n\n| Hydrogen | δ (ppm) |\n| --- | --- |\n| CH3 | 0.8–1.0 |\n| CH2 | 1.2–1.5 |\n| CH | 1.4–1.7 |\n| C=C–CHx | 1.7–2.3 |\n| O=C–CHx | 2.0–2.7 |\n| Ph–CHx | 2.3–3.0 |\n| ≡C–H | 2.5 |\n| R2 N–CHx | 2.0–2.7 |\n| I–CHx | 3.2 |\n| Br–CHx | 3.4 |\n| Cl–CHx | 3.5 ","cbCaif8WwFKhyq67","https://ap.wps.com/l/cbCaif8WwFKhyq67","pdf",304360,18,"English","# Question 1: 13C NMR signal prediction\n# Question 2: 1H NMR splitting pattern prediction\n# Question 3: IR spectrum identification and assignment\n# Question 4: Mass spectrum peak explanation (2-butanone)\n# Question 5: Structure identification from IR/13C NMR/1H NMR\n## Question 5 continued: unsaturation, symmetry, spectral interpretation, structure\n# Question 6: 1H NMR expected signals, shifts, and splitting\n# Question 7: Important resonance structures\n# Question 8: Predict major organic products for reactions\n# Question 9: Draw an arrow-pushing mechanism","[{\"question\":\"How do you predict the number of signals in a 13C NMR spectrum?\",\"answer\":\"Count chemically non-equivalent carbon environments in the molecule. Equivalent carbons (by symmetry) produce the same signal, reducing the total number of distinct 13C peaks.\"},{\"question\":\"What does the IR signal at about 1740 cm–1 suggest?\",\"answer\":\"A strong absorption near 1740 cm–1 indicates the presence of a carbonyl group typical of esters or related carbonyl-containing functional groups.\"},{\"question\":\"How can combined IR, 13C NMR, and 1H NMR shifts determine the structure of an unknown?\",\"answer\":\"Use IR to identify functional groups, use 13C NMR chemical shifts to locate specific carbon types (e.g., carbonyl vs alkene/alkane carbons), and use 1H NMR chemical shifts, integrations, and splitting patterns to assign hydrogen environments and connectivity. Together, these constraints allow the most consistent structure to be chosen.\"}]","CHEM 322 - Midterm 2 - Answer Key | PDF",1790071471,45]