1. Bonding and Structure in Solids
SCH4U

2. Structure in solids
Crystalline Solids: the atoms, ions, or molecules are ordered in well-defined three-dimensional arrangements. Have faces and make definite angles.
Amorphous solids: a solid in which particles have no orderly structure. There is no well-defined shape or face. Solids do not stack well together. Eg. Rubber or Glass

3. Crystalline vs. Amorphous Structures

4. Types of Solids
Solids are held tightly by significant intermolecular forces. We can classify solids based on the type of intermolecular force holding the together
1.Molecular Solids
2. Covalent Solids
3. Ionic Solids
4. Metallic Solids

5. **Structures of Crystalline Solids (AP) **
Each repeating unit is reffered to as a Unit Cell.
Unit cells create a crystal lattice.
Unit Cell 
Crystal Lattice 

6. Types of Unit Cells There are seven basic types of unit cells.
Cubic Unit Cell
Primitive Cubic
Body Centered Cubic
Face-Centered Cubic
Each has a different arrangement of lattice points.

7. Types of Unit Cells

8. Sample Problem
Determine the net number of Na+ and Cl- ions in the NaCl unit cell shown in the Figure.

9. Sample Problem
Determine the net number of Na+ and Cl- ions in the NaCl unit cell shown in the Figure.

10. Close Packing of Spheres
Arrangement of particles in closest contact to maximize attractive forces.
Hexagonal Close Packing ABAB pattern
Cubic Close Packing  ABCA Pattern

11. ** AP** Structure and Bonding in Metals* Extra Resources
ical_Chemistry/Physical_Properties_of_Matter/States_of _Matter/Properties_of_Solids/Crystal_Lattice/Closest_P ack_Structures
rystallinesolids.pdf
/10+IMFs%2CSolids+%26+Liquids.pdf
Read pages 8-9

12. 1. Molecular Solids Substances who’s particles are molecules.
Molecules are not strongly attracted together.
Intermolecular Forces include: London Dispersion Forces.
Some may include dipole-dipole forces and hydrogen bonding
Characterized by:
Low Melting and Boiling Points
Non-conductors

13. H-bonds become rigid, forming a lattice like structure
1. Molecular Solids
Examples include
Iodine, I2 (solid at room temperature)
Neon, Ne(m.p.=-248°C)
Solid CO2 ( mp °C )
Ice (H2O)
Sugar
H-bonds become rigid, forming a lattice like structure

14. 2. Metallic Solids
Metals have very strong intermolecular forces binding their atoms together  not fully understood.
Metals, are substances that typically have a very high melting point. Most have b.p of above 1000°C
Except Mercury  melts at -39°C
Gallium  melts at 30°C

15. 2. Metallic Solids
Valence electrons are typically in s or d sub-shell.
Electrons of neighboring atoms combine to form ‘electron soup’ that acts as a ‘glue’ to hold the positive nuclei of metal atoms together. These are called delocalized electrons.
The outer electrons are so weakly bound to metal atoms that they are free to roam across the entire metal. Having ‘lost’ their outer electrons, individual metal atoms are more like positive ions in a swarm of communal electrons.

16. 3. Metallic Solids
Electron Sea Theory is a theory that states that the electrons in a metallic crystal move freely around the positively charged nuclei

17. Rice Krispy Analogy!
Rice Krispy squares are an excellent analogy for metal solids. The marshmellow represents the delocalized electrons, and the rice are the positive metal ions.

18. Other Properties

19. 3. Ionic Solids
Substances who’s particles are ions --. Have completely given away or gained an electron.
An ionic compound is considered to be held by intramolecular forces.
Forms ions  opposite ions attract  ionic Bond

20. 3. Ionic Solids Some properties of metals include:
They have very high melting points
They are brittle; they do not bend and putting too much stress causes them to break
Soluble in Water
In a solid state, do not conduct electricity
In a liquid, or molten state, they are electrically conductive.

21. 3. Ionic Solids

22. 4. Covalent Network Solids
Consists of atoms held together by large networks or changes by covalent bonds.
Every atom is bonded forming a 3-D network
C & Si  tend to form covalent network solids.
Eg: Diamond, Graphite, Silica and Asbestos.
Very high melting points
Extremely hard substances
Poor conductors of electricity

23. Diamond Allotrope of carbon
Every carbon is bonded with 4 other carbons
Extremely high crystal lattice energy resulting in characteristic hardness and high melting point.

24. Graphite Allotrope of carbon
Each carbon forms a trigonal planar geometry
Crystal structure forms ‘sheets’ of covalently bonded carbons.
Sheets are not bonded together and as a result, slide over one another easily ( pencils! )
Unique fact:
Carbon is a nonmetal, but graphite conducts electricity!

25. Diamond vs Graphite

26. Quartz Crystal

27. Bonding in Crystalline Solids

28. Reminder: Test on Monday, October 30, 2017
Homework
SCH4U
In-Class Worksheet
Types of Solids Assignment
Design lab procedure for next class
Read 4.3 (p ) q’s p. 208 # 1-10
Chapter 4 Review  pg. 209 # 1-31
SCH4U- AP
Read 11.7 & 11. 8
Q’s pg. #
Reminder: Test on Monday, October 30, 2017

29. Test Topics SCH4U : Chapter : 4.1, 4.2, 4.3
Ionic, Covalent and Metallic Bonding
Lewis Structures
VSEPR Shapes
Polarity & Properties
Intermolecular Forces
Types of Solids
SCH4U : Chapter : 4.1, 4.2, 4.3
SCH4U- AP , , ,