many solids are crystals a solid in which the atoms are arranged in a regular pattern sodium...
TRANSCRIPT
Many solids are crystals
A solid in which the atoms are arranged in a regular pattern
Sodium chloride
Glass is an amorphous solid.
A solid in which the atoms are in no order. It is also brittle and shows a conchoidal fracture pattern, has hardness, and elasticity of shape.
Types of Glass
a. Soda-lime glass
most common commercial glass (90% of total production)
least expensive
b. Borosilicate glass
• strong• heat resistant • contains boron oxides
c. Tempered Glassmade stronger than soda-lime glass by rapid heating and cooling; used for side
and rear windows in cars
e. Soda-lead glass
• commonly called crystal or lead glass,
• expensive • widely used for the finest
tableware and art objects.
b. Class characteristics1. Flotation
Used to find the density of glass by floating glass particles in liquids of known densities.
Refractive index (RI)
Formula RI = velocity of light in vacuum velocity of light in medium
The RI of water at room temperature is 1.333
When the Becke line disappears
MATCH POINT The point at which the Becke line disappears
The RI of the glass = RI of the oil
b. First Fractures
• Form on the side of the glass OPPOSITE
the side of the penetrating object
• Radial fractures
c. Next Fracture
• Forms on the SAME side of the glass as the penetrating force
• Forms concentric fractures