This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: rose (kmr2427) – Homework 1 – fakhreddine – (51615) 1 This print-out should have 25 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 1.0 points Chloromethane (CH 3 Cl) forms a molecular solid. What type of forces hold it in a solid configuration? I) London forces II) dipole-dipole forces III) hydrogen bonding 1. III only 2. II and III only 3. I and II only correct 4. I only 5. II only 6. I, II, and III Explanation: Chloromethane is held in solid form by both London forces and dipole-dipole forces. 002 1.0 points What types of intermolecular interactions does chloroform (CH 3 Cl) exhibit? I) instantaneous dipole II) dipole-dipole III) hydrogen bonding IV) covalent bonding Recall that chloroform is tetrahedral elctronic geometry with C as the central atom. 1. II and III only 2. I, II, and III only 3. I and II only correct 4. II and IV only 5. II only Explanation: All molecules, because they have elec- tron clouds, experience instantaneous dipoles. CH 3 Cl is polar and thus experiences dipole- dipole interactions. CH 3 Cl does not contain any O H, N H, or F H bonds and therefore does not experience any hydrogen bonding interactions. Covalent bonding is an intramolecular interaction. 003 1.0 points Identify the dominant intermolecular force in the following species, respectively: RbCl , C 6 H 6 (benzene) , HI , Fe 2 O 3 , CH 2 NH . a) ionic forces b) hydrogen bonding c) dipole-dipole d) instantaneous dipoles 1. a, b, c, b, a 2. b, d, c, d, d 3. c, b, d, c, c 4. a, d, c, a, b correct 5. a, c, c, d, b 6. c, d, a, a, b 7. a, b, d, a, c Explanation: Rubidium Chloride and Iron(III) oxide are both ion-ion. Benzene is non-polar and thus has only van der Waal’s forces. Hydroiodic acid is polar and has dipole-dipole interac- tions. Methylimine has H-bonding. 004 1.0 points What is the strongest evidence for hydrogen bonding? 1. Hydrogen is able to accept or donate elec- trons, so it is the most versatile atom in the periodic chart. 2. Hydrogen has an extremely low elec- tronegativity. rose (kmr2427) – Homework 1 – fakhreddine – (51615) 2 3. Hydrogen can be considered either a metal or nonmetal. 4. The boiling points of NH 3 , H 2 O, and HF are abnormally high compared with the rest of the hydrides in their respective periods. correct Explanation: 005 1.0 points Order NaCl C 6 H 6 (benzene) CH 4 (methane) MgO H 2 O O 3 (ozone) by increasing evaporation rate. 1. H 2 O < C 6 H 6 < NaCl < O 3 < MgO < CH 4 2. C 6 H 6 < MgO < CH 4 < NaCl < H 2 O < O 3 3. CH 4 < C 6 H 6 < O 3 < NaCl < H 2 O < MgO 4. H 2 O < O 3 < MgO < C 6 H 6 < CH 4 < NaCl 5. C 6 H 6 < CH 4 < O 3 < H 2 O < MgO < NaCl 6. NaCl < CH 4 < O 3 < MgO < H 2 O < C 6 H 6 7. MgO < NaCl < H 2 O < O 3 < C 6 H 6 < CH 4 correct Explanation: 006 1.0 points Rank the compounds CH 3 OH CH 3 CH 2 OH CH 3 CH 2 CH 2 OH in terms of increasing evaporation rate....
View Full Document
- Spring '07