Jump to: navigation, search

Solids


Lesson: 141
Unit: 4
State Content Standard: Chemical Bonds

Lesson Title: Solids
Textbook page: Pages 456 - 460
Chemistry Passport: Page 156


Objectives

1. Students will learn about the different types of crystalline solids.
2. Students know about bonding in solids.

Lesson Content
A solid is one of the three states of matter. Solids have a fixed volume and a definite shape.
Most solids have a definite melting point.
The properties of solids are determined by the nature of the forces that hold them together.
There are a couple different types of solids, these include:
Crystalline Solids- Solids with regular arrangements of their components. The arrangements of the components in a crystalline solid produce beautiful, regularly shaped crystals.
Crystalline Solids are separated into 3 different classes.
Ionic Solids- Ionic solids are solids in which oppositely charged atoms or groups of atoms stick together via electrostatic attraction. When this happens, they form big beautiful crystals.
Molecular Solids- Molecular Solids are formed when covalent molecules are held together by intermolecular forces.
In this type of bonding, the intermolecular forces between the molecules are strong enough to keep the molecules in place.
These types of solids have a much lower melting and boiling point than any other solid; this is because the intermolecular forces holding the molecules together are much weaker than those of the bonds in the other compounds.
This type of bond occurs in ice.
Atomic Solids- Atomic solids occur when noble gases are cooled to extremely low temperatures and lock themselves in place using very weak London dispersion forces.
London dispersion forces are the weakest intermolecular force
We would never run into these kinds of solids in real life because we need extremely low temperatures to see them.
Amorphous Solids- Amorphous solids, unlike any other solids do not have a crystal like structure.
In Amorphous solids, the particles are just stuck all over the place with no specific pattern.
Some amorphous solids are soft and rubbery because they are made of long molecules which are just kind of tangled together and bound together by intermolecular forces.
Glass is a type of amorphous solid.

Diagram



Definitions(Both textbook definitions and in your OWN words
Solids are one of the three states of matter, it is firm and hard. It has a definite shape and volume.

Example Problems (Minimum of 5 problems with answers in red)
1. Do solids have a fixed volume and shape? – Yes.
2. Two solids in contact will experience very _____ rates of diffusion. – Slow.
3. What are two main types of solids? - Crystalline & Amorphous Solids.
4. Do solids have a definite melting point? – Yes.
5. Define melting in solids. – Melting is the physical change of a solids to a liquid by the addition of heat.

State Released Test Question

If the attractive forces among solid particles are less than the attractive forces between the solids and a liquid, the solids will?
A.Probably form a new precipitate as its crystal lattice is broken and re-formed.
B.Be unaffected because attractive forces within the crystal lattice are too stronq for the dissolution to occur.
C.Begin the process of melting to form a liquid.
D.Dissolve as particles are pulled away from the crystal llatice by the liquid molecules.

The answer is, D. Dissolve as particles are pulled away from the crystal llatice by the liquid molecules.

Reference


Download Lesson

(Flipchart) | (Flipchart PDF) | (PPT) | (MS-Word) | (PDF)



Continue to Next Lesson: Liquids




Do you see an error on this page? Please create an account and help us edit this page. Your help is greatly appreciated.