1. 1. What intermolecular forces have we covered so far (there are three)? 2. Briefly describe each. Day 5 1-7

2. C. London Dispersion Forces 1. London dispersion forces exist between _________ _________ and are found in ____ ___________ 2. Induced dipoles and instantaneous dipoles arise when the ________ clouds of atoms or molecules are _________ by an outside influence such as a collision. nonpolar particles All substances electron distorted

3. 3. Polarizability is the _____ in distorting or “squashing” the electron cloud. 4. The _________ of the dispersion forces depends upon several factors ________ of _________ - more electrons = more polarizable (easier to distort)  stronger dispersion forces ease strength numberelectrons He vs. Ne

4. 4. The _________ of the dispersion forces depends upon several factors _____ or ____ - more mass = more polarizable (easier to distort)  stronger dispersion forces strength masssize CH 4 vs. C 6 H 14

5. D. Hydrogen Bonding 1. Hydrogen bonding is the attraction of an atom of _________ from one molecule to an atom with a high ________________ in another molecule, especially __, __, & __. hydrogen electronegativity F O N

6. 2. Hydrogen bonds affect compound characteristics such as _____________ _________________________________ 3. Diagram an example: H 2 O mixed with NH 3 and HF (see also p 390) boiling point, phase at room temp., shape ( DNA ), density  see C and H p 391

7. 1. In the table above the boiling points increase with _________________ molecular weight because the London dispersion forces are _________________. 2. Which of the following substances is most likely to exist as a gas at room temperature and normal atmospheric pressure: P 4 O 10, Cl 2, AgCl, I 2 ? Noble GasBoiling Point (K) He4.6 Ne27.3 Ar87.5 Kr120.9 Xe166.1

8. E. van der Waals Forces is an umbrella term for the intermolecular forces _________________, ____________, and __________________. F. How do the intermolecular forces compare in strength? london dispersiondipole-dipole hydrogen bonding london < dip.-dip. < H-bond < ion-dip. < ion-ion (for solids)

9. Why do compounds with strong intermolecular attractive forces have higher boiling points than compounds with weak intermolecular forces? Day 6 1-8

10. page 257 #s 64, 65, 66, 67 … page 181 = electronegative values Ammonia = NH 3

11. 1. Read the half sheet on Self-cleaning windows and answer the question at the bottom. Day 1 1-9

12. Periods 1 & 3 = Monday 1-14 day 4 Day 6 1-8

13. E. van der Waals Forces is an umbrella term for the intermolecular forces _________________, ____________, and __________________. F. How do the intermolecular forces compare in strength? london dispersiondipole-dipole hydrogen bonding london < dip.-dip. < H-bond < ion-dip. < ion-ion (for solids)

14. III. Properties of Liquids A. Viscosity is a liquid’s ____________ to _____. 1. Higher viscosity indicates _____________, ___________, & _______________ resistance flow “thickness”slow flow Strong bonds

15. 2. Lower viscosity indicates ____________, __________, & _____________ 3. Temperature affects viscosity. a. How? b. Why? “thinness”fast flow weak bonds - T up, KE up, movement/flow up - T up, viscosity down,

16. Chapter 11 Homework # 1 – 10 correct http://wps.prenhall.com/esm_bro wn_chemistry_9/2/660/169060.cw /index.html

17. Day 2 1-10 1. Which liquid should be more viscous at room temperature honey or rubbing alcohol? 2. What if the honey is cooled by 10 degrees and the rubbing alcohol is heated by 10 degrees? 3. What intermolecular forces exist for NH 3 ? Put them in increasing order of strength.

18. Periods 1 & 3 = Tuesday 1-15 Day 5 Day 2 1-10

19. B. Surface Tension 1. Surface tension = net ________ force on the particles at a _________ surface a. “Skin” is visible as molecules are ________ __________. b. Creates ___________ shape and less _________ ______ inward liquid’s packed together surfacearea spherical

20. 2. Capillary action is a liquid’s rising in a _________ ______ until cohesive and adhesive forces _________. Examples: narrow tube balance

21. 3. Meniscus shape depends on strengths of cohesion versus adhesion. a. H 2 O  shape indicates stronger ___________ and weaker __________ b. Hg  shape indicates stronger __________ and weaker ___________ cohesion  adhesion  adhesioncohesion adhesion water sticking to water water sticking to another polar substance

22. IV. Vapor Pressure A. Vapor pressure is the pressure just above the _________ of a _______ or ______ as the particles escape into the air. B. Volatility 1. Liquids that are volatile ___________ easily. surface liquid solid evaporate

23. 2. Volatility depends on _________________, ________________________, vapor pressure intermolecular forces Higher vapor pressure = MORE volatile Weaker intermolecular forces of attraction = MORE volatile

24. 2. Volatility depends on ______________, and ______________. C. Boiling 1. ______ ___________ = __________ __________ size / weight temperature vapor pressureexternal pressure

25. C. Boiling 2. What obstacles must a water molecule overcome in order to boil? Intermolecular forces, especially H bonds (love of neighbors & family) Surface tension (surface sentinels  who goes there?) Pressure from outside (kept down by “the Man”)

26. 1. How could we get water to boil withOUT changing temperature? 2. Which is more volatile water or methane? Explain reasoning! methane = 1-11 Day 3

27. Page 257 #s 70 and 75 (all parts) page 257 #s 64, 65, 66, 67 … page 181 = electronegative values Ammonia = NH 3 Due Friday 1-11

29. Critical temperature – the highest temp. at which a substance can exist as a liquid (greater intermolecular attractive forces = higher critical temp.  substance would rather be liquid) critical pressure – pressure necessary to achieve liquid at critical temp. Triple point – temp. at which solid, liquid, and gas phases coexist in equilibrium

33. * During a phase change, temperature does NOT change (slope = 0) AS WE HEAT A SOLID!

34. Chapter 11 Homework # 2 – 11 correct http://wps.prenhall.com/esm_ brown_chemistry_9/2/660/16 9060.cw/index.html 1-11 Day 3