Chemistry 110 Name PRACTICE EXAM 2C 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 2C 1 A neutral atom has the following electron configuration What is the maximum number of covalent bonds this atom could form with hydrogen atoms A 1 B 2 C 3 D 4 E 5 2 How many valence electrons and lone pairs are in the structure of the N2H4 molecule lone pairs A valence electrons 10 B 14 2 C 14 1 D 10 2 E 12 3 1 3 Which of the following is the most polar bond A O F B C S C N F D C H E B F 4 Which of following would have the highest dipole moment A HF B HCl C HBr D HI E All have the same dipole moment because they all contain H 5 For which molecule is it not possible to draw a Lewis structure which follows the octet rule A B C D E HF CH2Cl2 N 2O 4 O3 PCl5 6 Which of the following molecules has the longest C C bond and the weakest C C bond C2F6 A B C D E longest bond C2F2 C2F2 C2F4 C2F6 C2F6 C2F4 C2F2 weakest bond C2F2 C2F6 C2F4 C2F6 C2F2 7 Which of the following contains both ionic and covalent bonds A B C D E ClF SO2 NaCl SO3 NaCN 8 Which of the following formulas may represent a cycloalkane with only one ring A C2H2 B C6H6 C C6H14 D C6H12 E C5H12 9 What functional groups are present in the following aromatic molecule H N i ii iii iv v A B C D E ketone amine alcohol aldehyde carboxylic acid HO O OH ii iii and v i ii and iv ii iii and iv i ii and iii ii iv and v 10 Which of the following is not an isomer of the others 11 What are the hybridizations of carbons labeled 1 and 2 in a caffeine molecule shown below A B C D E Hybridization of C1 sp2 sp3 sp2 sp3 sp C2 sp2 sp3 sp sp2 sp2 12 Which of these molecules contains an odd number of electrons i ii iii A B C D E NO ClO2 NO2 i only ii only iii only i and iii only All three contain an odd number of electrons 13 Identify the molecules that have a zero net dipole moment i ii iii CS2 CH2O SeF2 A i only B i and ii only C i and iii only D ii and iii only E i ii and iii 14 Which of the following molecules has a trigonal bipyramid electron domain geometry A NF4 B SeF42 C PF4 D SF4 E XeF4 15 C N and O atoms readily form multiple bonds with each other Which of these statements correctly explains why larger atoms in period 3 do not readily form multiple bonds with each other i The d orbitals that become available in period 3 atoms such as Si P and S get in the way and block the formation of multiple bonds ii The energy required to promote electrons to p orbitals in Si P and S is so large than that the atomic orbitals cannot hybridize iii Unhybridized p orbitals on Si P and S cannot form multiple bonds because the atoms are too large for the porbitals to overlap A B C D E i only ii only iii only i and iii all three 16 What are the electron domain and the molecular geometries of SnCl3 A B C D E electron domain geometry trigonal pyramidal trigonal planar tetrahedral tetrahedral trigonal planar molecular geometry tetrahedral trigonal pyramidal tetrahedral trigonal pyramidal trigonal planar 17 Which of the following molecules are not linear i ii iii iv H 2O CO2 C2H 2 C2H 4 A i and ii only B ii and iii only C i and iii only D iii and iv only E i and iv only 18 How many and bonds are in the molecule shown below A B C D E 18 8 6 18 8 2 2 2 3 1 19 Which of the following molecular ions has delocalized bonds A SO22 B CO32 C SiO44 D OH E PO33 20 What is the O by mass in the molecule below A 40 0 B 41 8 C 53 3 D 58 2 E 60 0 21 Which one of the following organic molecules has the same empirical formula as benzene benzene H A B C H D E 22 An unknown sample weighs 2 1 g and contains 0 035 moles of molecules Identify the molecule A B C N O O OH D E O HO O OH 23 How many structural isomers can be drawn for C5H12 A 1 B 2 C 3 D 4 E 5 24 Which one of the following compounds can exist as cis trans isomers 25 Consider the neutral molecule with the molecular formula ClOF3 Chlorine is the central atom and the remaining four atoms are directly bonded to Cl One of the F Cl F angles in this molecule is 175 i e approximately 180 Based on this information select the incorrect statement from the choices below A The molecular geometry of ClOF3 is best described as approximately square planar B ClOF3 has one non bonding electron pair on Cl C The three O Cl F angles in this molecule are approximately 90 90 and 120 D The electron domain geometry about the Cl atom is trigonal bipyramid E Every Lewis structure that can be drawn for ClOF3 violates the octet rule 26 In the capsaicin molecule below the main capsaicinoid in chili peppers rank the angles indicated in order of increasing bond angle Hint Lone pairs are not explicitly shown A 1 3 2 B 1 2 3 C 2 3 1 D 1 3 2 E 1 2 3 27 The energy of a covalent bond between two atoms is shown below as a …