Chemistry 110 Name Practice Exam 2B Section Midterm 2 Signature IMPORTANT On the scantron answer sheet you MUST clearly fill your name your student number section number and test form white cover test form A yellow cover test form B Use a 2 pencil There are 28 questions on this exam Check that you have done all of the problems and filled in the first 28 bubbles on the scantron The maximum score on this exam is 28 points Your score will be reported in percents max 100 Exam policy This cover sheet must be signed and handed in with your answer sheet for your exam to count Calculators with text programmable memory are not allowed Relevant data and formulas including the periodic table are attached at the end of this exam Your grade will be based only on what is on the scantron form The answer key will be posted on the web after the exam under Exam Schedule Hints As you read the question underline or circle key words to highlight them for yourself Avoid errors from mis reading the question Pay attention to units and magnitudes decimal places of numbers obtained from calculations There is no penalty for guessing CHEMISTRY 110 PRACTICE EXAM 2B 1 How many valence electrons and lone pairs are in the structure of the ammonium ion A B C D E valence electrons 8 10 8 10 12 lone pairs 0 1 1 2 3 2 Which of the following best represents the molecular structure of the molecule COS A I B II C III D II and III are equally good representations E I and II are equally good representations 3 What is the arrangement of electron domains about the central atom in formaldehyde H2CO A Tetrahedral B Trigonal planar C Square planar D Trigonal bipyramidal E Linear 4 Which of these molecules is are non polar Cl Cl Cl Cl Cl Cl Cl Cl Cl I II III IV A I only B II only C IV only D I and IV E II and III 5 What functional groups are present in the molecule below A alcohol amine aldehyde B amine aldehyde ketone C amine ketone carboxylic acid D alcohol ketone carboxylic acid E ketone carboxylic acid ester 6 What is the correct molecular formula for the following molecule A C4H8O2 B C4H10O2 C C5H8O2 D C5H10O2 E None of the answers listed here are correct 7 Of the following which element is the most electronegative A Ca B At C O D Al E Li 8 Which one of the following molecules is nonpolar A NH3 B OF2 C CH3Cl D H2O E BeCl2 9 What is the hybridization of As in the AsF4 ion A sp B sp2 C sp3 D sp3d E sp3d2 10 Hydrocarbons with 6 carbons in their longest chain have a parent name hex for six Which hydrocarbon has the same empirical formula as cyclohexane A benzene B hexane C benzane D hexyne E hexene 11 The structure of citric acid is given below What is the hybridization of the two labeled carbons A 1 sp 2 sp2 B sp2 sp3 C sp3 sp2 D sp3 sp E sp2 sp2 12 What is the percent carbon by mass in the compound below A 39 4 B 42 2 C 51 7 D 56 3 E 62 3 13 Select the electron domain geometry and molecular geometry of chlorine in the perchlorate ion ClO4 A Electron domain geometry trigonal planar molecular geometry tetrahedral B trigonal planar trigonal planar C tetrahedral tetrahedral D trigonal pyramidal trigonal pyramidal E trigonal pyramidal trigonal planar 14 Which of the following molecules are isomers A I and II only B II and III only C I and IV only D I II and III E All of them 15 Fill in the blanks As bond order increases the strength of a covalent bond and bond length strength A increases length increases B decreases decreases C increases decreases D decreases increases E increases remains constant 16 Which of the following have one or more atoms in the structure that have exceptions to the octet rule BF3 NF3 SiF4 XeF4 A BF3 and NF3 B NF3 and SiF4 C SiF4 and XeF4 D BF3 and XeF4 E NF3 and XeF4 17 Which bond in the molecule below is the most polar H A C H B C Cl H C C Br D C O E C F C C C F Cl C C C Br OH 18 Which of the following molecules has a trigonal planar structure 1 CO32 2 SOCl2 3 H3O 4 SO3 A 1 only B 1 and 4 C 1 2 and 3 D 1 3 and 4 E all 4 19 Rank the indicated bond angles in the molecule shown below in order of increasing bond angle Lone pairs are NOT explicitly shown 1 H O 3 H C C O H 2 4 O H N H A 1 4 3 2 B 3 1 2 4 C 4 1 2 3 D 4 1 2 3 E 3 4 1 2 20 What is the total number of and bonds in the following molecule H C C C C C N A 6 3 B 3 3 C 6 6 D 3 6 E 3 9 21 Which of the following molecules will exhibit delocalized bonding I SO II SO2 III SO3 A I only B II only C III only D I and II E II and III 22 What is the electron domain geometry of a molecule that only contains S and F and is 29 67 S by weight A Octahedral B Trigonal planar C Linear D Tetrahedral E Trigonal bipyramidal 23 Draw Lewis structures for NO2 NO2 and NO3 Based on the interpretation of the Lewis structures put these in order of increasing bond order A B C D E NO2 NO2 NO3 NO2 NO3 NO2 NO2 NO3 NO2 NO3 NO2 NO2 NO2 NO2 NO3 H 24 H CH C CH 3 OH C H How are the molecules below related to the molecule shown above Are they a geometric isomer a structural isomer or neither O H C C H CH3 H C H 3C C H I CH H OH H 3C C H C CH3 II CH C H H III I II III A neither structural geometric B neither geometric structural C geometric geometric structural D structural structural geometric E geometric structural geometric OH 25 Which of the following are pairs of resonance structures A I only B II only C III only D I and II E II and III 26 Which of the following contains the largest H X H bond angle where X is the central atom of the molecule A BF3 B SiCl4 C NH3 D H2O E They all have the same bond angle 27 Which statements concerning the molecule below are true i The molecule is especially stable because it has resonance ii All carbons are sp hybridized iii The carbon carbon bond lengths are all the same A B C D E i only ii only iii only …