Concept Summary

1

Solids

• Concept Summary
• Batesville High School Science

2
Crystals

• Crystals are regular geometrical arrangements of
  atoms.
• Most metals have a regular crystalline structure.
• Many minerals are crystals.

3
Size of Crystals

• Many crystal structures are evident to the naked
  eye.
• Quartz, copper sulfate, galvanized tin, etc.
• Many crystals can be seen only under a
  microscope.
• NaCl, etc.
• Many sub-microscopic crystals are revealed by
  x-ray diffraction.

4
Density

• Density measures how much matter is packed into a
  unit space.
• Density depends on the masses of the atoms and
  how closely they are packed together.
• Density Mass/Volume

5
Density

• Density of liquid water 1.00 g/cm3
• Density of water ice 0.92 g/cm3
• Densest material on Earth is osmium
• Density of osmium 22.6 g/cm3

6
Weight Density

• Weight density is often used to compare liquids.
• Weight density weight/volume

7
Specific Gravity

• Specific gravity is another measure of density.
• Specific gravity
• Since density of water 1.00 g/cm3, specific
  gravity numerical density

Density of the substance
Density of water
8
Elasticity

• When a substance returns to its original shape
  after being deformed, it is elastic.
• If an elastic material is stretched beyond its
  elastic limit, it will remain permanently
  deformed.
• Stretch is proportional to force
• Hookes Law

F kx
9
Compression Tension

• Compression is squeezing.
• Tension is stretching.
• Beams can be both under tension and compression
  at the same time.
• Top under tension, bottom under compression, or
  vice versa.
• I-beams.

10
Scaling

• Scaling studies how size affects, weight,
  strength, and surface area.
• Strength is proportional to cross-section area
• Heat transfer is proportional to surface area.
• Weight is proportional to volume.
• Food requirement is proportional to volume.

11
Scaling

• Double each side of a cube.
• It has 4 ( 22) times the cross section
• 4 times the strength
• It has 4 ( 22) times the surface area
• 4 times the heat loss/gain
• It has 8 ( 23) times the volume
• 8 times the weight
• Needs 8 times the nutrients

12
The End