CHM 1040 F2012 Sample Exam 2 Use the following molecule for questions 1-3. F Cl N Cl 1. What is the molecular geometry around the central N atom? a) tetrahedral b) trigonal planar c) trigonal pyramidal d) bent 2. What is the electronic geometry around the central N atom? a) tetrahedral b) trigonal planar c) trigonal pyramidal d) bent 3. How many polar bonds are present in this molecule? (EN values: N = 3.0; Cl = 3.0; F = 4.0) a) 0 b) 1 c) 2 d) 3 4. Which of the following molecules is non-polar? (EN values: C = 2.5; H = 2.1, N = 3.0; Cl = 3.0) CH3 H3C a) H3C CH3 C CH3 C Cl b) Cl CH3 c) N N Cl Cl CH3 d) H3C CH3 CH3 5. What is the strongest type of intermolecular force between CH3OH and CH3Cl? a) hydrogen bonding b) dipole-dipole c) dipole-induced dipole d) dispersion forces 6. Which of the following pairs of molecules will not engage in hydrogen bonding with each other? a) ammonia (NH3) and CH4 b) HF and H2O c) HF and CH3OH d) CO2 and H2O 7. Which of the following combinations would be the least soluble? a) ammonia in water b) KI in C6H14 c) C6H14 in C6H6 8. How many moles of H2O are present in 90.0 g of H2O (FW = 18.0g/mol)? a) 90.0 mol b) 72.0 mol c) 5.0 mol d) HCl in water d) 0.20 mol 9. How many grams of NaCl should be dissolved in 465 mL of solution to obtain a concentration of 18.0% (w/v)? a) 2583 g b) 83.7 g c) 25.8 g d) 5.55 g 10. What volume of a 12.5%(w/v) solution of sugar is needed to deliver 42.0 g of sugar? a) 336 mL b) 2.4 mL c) 5.25 mL d) 3.36 mL 11. What is the formula weight for K2SO4? a) 135 g/mol b) 174 g/mol c) 270 g/mol 12. Which of the following is a heterogeneous mixture? a) jell-o b) salt water c) coffee d) 183 g/mol d) ice cream 13. A solution contains 50 g of water and 55 g of acetic acid, which of the following is not true? a) water is the solute b) acetic acid is the solute c) acetic acid is the solvent d) none of the above 14. Which of the following molecules will have the strongest dispersion forces? a) CH4 b) C2H6 c) C3H8 d) C10H22 15. Which of the following is not an intermolecular force? a) dipole-dipole b) hydrogen bonding c) ionic bonding d) dispersion 16. Which of the following molecules cannot participate in hydrogen bonding as either a donor or acceptor? a) HCl b) HF c) H2O d) H3C-O-CH3 (dimethyl ether) 17. Molarity is equal to mol/L. a) True b) False 18. An alkane is best described as… a) containing any number of C=C double bonds. b) containing any number of C≡C triple bonds. c) a molecule that burns well. d) a molecule that is saturated. 19. Which of the following is not true regarding organic molecules. a) They are based on a carbon backbone. b) Most of them are water soluble. c) The majority are covalently bonded. d) They act as insulators. 20. Which of the following is the line-bond representation for 1-chlorobutane. a) Cl Cl b) c) Cl d) CH3 21. Consider the molecule below. The indicated carbon atom is classified as… a) primary, 1° b) secondary, 2° c) tertiary, 3° d) quaternary, 4° 22. How are the following two molecules related? F F a) geometric isomers d) simple isomers F F b) constitutional isomers c) structural isomers 23. Which of the following is 3,4-dimethyldecane? a) b) c) d) 24. Which of the following is the geometric isomer of a) b) c) d) 25. Which of the following statements is true regarding constitutional isomers? a) They have the same connectivity in space. b) They have the same physical properties (boiling points, etc.) c) They are cis/trans isomers. d) They have the same formula. 26. A generic name for a monosaccharide with six carbons is a. Octose b. Triose c. Tetrose d. Hexose 27. Is this sugar a ketose or aldose? a. Ketose b. Aldose 28. Is this the D- or L- form of xylose? a. D b. L 29. Is this the - or -anomer of glucose? e. Alpha () f. Beta () 30. What kind of glycosidic bond is holding this disaccharide together? a. -1,4 b. -1,6 c. -1,4 d. None of the above 31. A molecule that loves water is called a. Hydrophilic b. Hydrophobic 32. Soap molecules form this structure in water a. Liposome b. Phospholipid bilayer c. Vesicle d. Micelle