Class Notes (837,186)
United States (324,898)
Chemistry (599)
CH 301 (158)
Sutcliffe (5)
Lecture

H11- Solids and Liquids-solutions.pdf

6 Pages
123 Views
Unlock Document

Department
Chemistry
Course
CH 301
Professor
Sutcliffe
Semester
Spring

Description
ngac (ttn793) – H11: Solids and Liquids – mccord – (51600) 1 This print-out should have 25 questions. Multiple-choice questions may continue on 1. None of these the next column or page – find all choices before answering. 2. armed forces. 3. intramolecular forces. 001 10.0 points What would be the most significant type of intermolecular forces in a liquid sample of 4. intermolecular forces. correct fluoroform (CHF )?3 Explanation: Bonds within molecules or formula units are 1. ionic called intramolecular forces. Bonds between 2. hydrogen bonding particles are called intermolecular forces. 3. dispersion 003 10.0 points What is the predominant intermolecular force 4. dipole-dipole correct between IBr molecules in liquid IBr? 5. covalent 1. ionic forces Explanation: 2. hydrogen bonds London forces, dispersion forces, van der Waals or induced dipoles all describe the same 3. dispersion forces correct intermolecular force. London forces are in- duced, short-lived, and very weak. Molecules 4. covalent bonds and atoms can experience London forces be- cause they have electron clouds. London 5. dipole forces forces result from the distortion of the elec- tron cloud of an atom or molecule by the Explanation: presence of nearby atoms or molecules. You might have thought that dipole forces Permanent dipole-dipole interactions are was right. The fact is that the dipole be- stronger than London forces and occur be- tween iodine and bromine is incredibly weak tween polar covalent molecules due to charge -owekoacntfhettati separation. compound is a liquid. Another FACT is that H-bonds are a special case of very strong dispersion forces are the dominant forces here dipole-dipole interactions. They only occur due to the SIZE of these atoms and hence when H is bonded to small, highly electroneg- molecule. Just know that not ALL dipole ative atoms – F, O or N only. forces are bigger than any set of dispersion Ion-ion interactions are the strongest due to forces. Size matters, and dispersion forces extreme charge separation and occur between win out here. ionic molecules. They can be thought of as both inter- and intramolecular bonding. 004 10.0 points CHF i3 a polar molecule that does not con- Which of the following structures represents tain H bonds; therefore, dipole-dipole forces apossiydrogenbond? will be the most significant type of intermolec- ular forces present. 1. Cl H ··· Cl 002 10.0 points 2. C H ··· O Forces between particles (atoms, molecules, or ions) of a substance are called 3. F H ··· F correct ngac (ttn793) – H11: Solids and Liquids – mccord – (51600) 2 4. Br H ··· Br 6. 0.35 correct Explanation: Explanation: H-bonds are a special case of very strong rCa=100pm rIn =72pm ▯|z|µ dipole-dipole interactions. They only occur The energy E p , so the ratio is when H is bonded to small, highly electroneg- r2 ative atoms – F, O or N only. 2 ECa |Ca |rIn |2|(72 pm)2 005 10.0 points E = 2 = |3|(100 pm)2 =0 .3456 Identify the kinds of intermolecular forces In |In|rCa that might arise between molecules of CH 3H. 007 (part 2 of 2) 10.0 points Which ion will attract a water molecule more strongly? 1. dipole-dipole 2. London forces, dipole-dipole 1. In3+correct 3. London forces, dipole-dipole, hydrogen 2. Equal attraction bonding correct 3. Ca2+ 4. None of these Explanation: 2+ The attraction of the Ca ion will be less 5. London forces than that of the In+ ion because it has both alargerradiuwerharge. 6. hydrogen bonding 008 10.0 points Explanation: H If the interaction between two species is pro- portionalto 1 ,whichofthefollowingislikely r3 H C O Hsi.r involved? + H 1. Na and H O2 006 (part 1 of 2) 10.0 points 2. ions in an ionic solid Calculate the ratio of the potential energies 3. bromine molecules in the liquid phase for the interaction of a water molecule with a 2+ 3+ Ca ion (of radius 100 pm) and with an In 4. chloromethane molecules in the liquid ion (of radius 72 pm). phase 1. 0.63 5. chloromethane molecules in the solid phase correct 2. 0.24 Explanation: 1 3. None of these 3 ▯ E por dipole-dipole interactions. r 4. 0.52 009 10.0 points Which of the following can form intermolecu- 5. 0.76 lar hydrogen bonds? ngac (ttn793) – H11: Solids and Liquids – mccord – (51600) 3 and +3 cations will generally form hydrates. + 1. PH 3 Na will also attract water due to its smaller size. 2. (CH ) NH correct 3 2 012 10.0 points 3. H 2O Adpouldstveaar shape due to the property of 4. CH 3OCH 3 1. capillary action. Explanation: Only molecules with H attached to the electronegative atoms N, O, and F can hy- 2. vapor pressure. drogen bond. Of the molecules given only (CH 3 2H h2s the H directly bonded to N, 3. close packing. so it can undergo hydrogen bonding. 4. surface tension. correct 010 10.0 points 5. viscosity. Which of the following cations is likely to be hydrated in compounds? Explanation: + Molecules on the surface of a liquid are 1. Rb influenced by intermolecular attractions to- wards the interior; these attractions pull the 2. NH + 4 surface layer toward the center. The most sta- + ble situation is one in which the surface area 3. K is minimal. For a given volume, a sphere has + the least possible surface area. 4. Cs 013 10.0 points 5. Li correct Surface tension describes Explanation: + 1. the inward forces that must be overcome Li is the smallest. in order to expand the surface area of a liquid
More Less

Related notes for CH 301

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit