Earth’s materials are being used up at a quicker rate than they can be replenished We must find...

Earth’s materials are being used up at a quicker rate than they can be replenished

We must find substitutes for common materials

Substitutes should be Plentiful Inexpensive Properties are very similar to the original

material

An element that at different forms each has a distinctly different physical or chemical property

Example: Diamond, graphite, and buckmisterfullerene are ALL Carbon!

Ceramics Clay (mineral kaolinte, magnesium, sodium,

and potassium ions) Very plentiful on earth Natural ceramics: hard, ridged, low

chemical reactivity, resistance to wear, resistant at very high temperatures, strong at high temps▪ Diesel engines made from ceramics can operate

at higher temps

Problems – ceramics are brittle and crack when go from hot to cold quickly

Plastics Synthetic materials made of carbon

chains with hydrogen and other materials attached

Less dense than metal Springy (doesn’t dent easily) Problem: most plastics are made from petroleum (a non-renewable resource)

Alloys A solid combination of 2 or more metals Brass = zinc and copper Bronze = copper with tin, zinc, and other

elements Steel = iron with carbon and small

amounts of others Other common alloys: Pewter, 14-

carat gold, white gold

Paint, Varnishes, and Shellacs Protects Look Nice Powder Coating▪ Eliminates the need for solvents▪ Electrically charged fine powder is sprayed from spray

guns▪ Product is heated to “cure” the powder into a tough

shell▪ Long-lasting, corrosion resistant surface

Paints are made of▪ Pigment and solvent

Process used to cover one metal with another

Ex. Steel bumpers on trucks are plated with nickel so they resistance rusting in bad weatherProcess is all about the oxidation and reduction of the metalsEx. Chrome plating on trucks and

motorcycles

One or two atoms thick…very thin!Optics and electronics industryUV /anti-glare protection on auto

glassColor changing paint (iridescence)

Cars that appear different colors in different light

Page 204 - 205#’s 1, 3, 5, 7, 8, 14, 15, 16, 17

Test Friday 2-29-08 Unit 2 Section C and D Balancing Equations What is the mole Molar Mass Conserving Resources Dealing with Waste 4 R’s This Power Point

Remember to complete your review Questions for both sections: due the day of the test