Esp - Chemistry I - Exam Ii - Answers

EST – Chemistry I – Exam II – October 28th, 2009 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.

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True or False: Potassium Iodide would have a higher melting point than Magnesium Chloride. True or False: The name for FeO is Iron Oxide. True or False: Electron affinity for noble gases is positive. True or False: As3+ has a noble gas electron configuration. True or False: Nitrogen gas has 1  and 2  bonds. True or False: There are 6 valence electrons in Iron. True or False:  bonds are formed from overlapping of adjacent hybridized orbitals. True or False: SF5- is AX5. True or False: The octet rule is always fulfilled. True or False: Lone pairs causes the angles to decrease between atoms. True or False: The name for PCl5 is monophosphorous pentachloride. True or False: An electronegativity difference of 0.5 means the bond is non-polar. True or False: Resonance is moving atoms around. Which of the following is the name of the compound correctly paired with its symbol, scientifically? a. BeOH (beryllium hydroxide) b. V2O5 (Vanadium (II) Oxide) c. TiO2 (Titanium (II) Oxide) d. H2O (water) e. None of the above What is the name of this compound, Cu(ClO4)2? a. Copper (I) Perchlorate b. Copper (I) hyperchlorate c. Copper (II) Perchlorate d. Copper (I) Chlorite e. None of the above Which of the following periodic trends statement is incorrect? a. Electron affinity becomes more negative from left to right across the periodic table. b. Ionization decreases with increasing atomic number within each column. c. Atomic radius increases with increasing atomic number within each column. d. Electronegativity becomes greater from bottom right to top left. e. None of the above. Which of the following bond is most polar? a. S-Cl b. S-Br c. Se-Cl d. Se-Br e. You can’t tell from information given. How many resonance structures are there for O3? a. 1

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b. 2 c. 3 d. 4 e. None of the above How many unpaired electrons are on the carbon in CO2? a. 0 b. 1 c. 2 d. 3 e. 4 What is the hybridization on the carbon atoms in C2H4? a. sp, sp b. sp2, sp3 c. sp3, sp3 d. sp2, sp2 e. none of the above. Which of the following does not obey the octet rule in its lewis structure? a. CCl4 b. O3 c. PBr5 d. BCl3 e. Both C and D What is the hybridization of S in the following lewis structure of H 2SO4? a. sp b. sp2 c. sp3 d. sp3d e. None of the above.

23. Which of the following has correct formal charge? (in case confusing: a) acrylonitrile b) BF3 c) CClO d) Benzene C6H6)

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d. e. None of the above 24. What is the molecular shape of SO3? a. Linear b. Tetrahedral c. Trigonal pyramidal d. Trigonal bipyramidal e. None of the above – It is trigonal planar

25. What is the formal charge on Br in BrO2a. +1 b. -1

c. +2 d. -2 e. None of the above 26. What is the electron domain geometry of BH2-? a. Bent b. Trigonal Planar c. Linear d. Tetrahedral e. None of the above

27. Which of the following is correct? a. H(-) – F(+) polar + b. C ( ) – H ( ) polar + c. Na ( )– Cl( ) ionic d. O (-)– H(+) polar e. None of the above 28. Identify the third-row elements, X, that form the ion:

a. C b. N c. Ge d. Si e. None of the above. 29. Which of the following molecules can NOT rotate freely? a. C3H8 b. H2O c. C2H4Cl2 d. C2H4 (due to double bond, can not rotate around double bond) e. None of the above 