Silver (Ag)

Student Objectives: Students will learn the principal features of silver and why these make silver both useful and valuable.

Tips for the Teachers: Discuss the meaning of “ornament” and the use of silver for this purpose.

Suggested Activities:

1. Bring in hand mirrors to observe reflectivity. Bounce the sun’s rays, laser pointer, or flashlight beam onto a wall or floor. (Caution: To avoid eye damage, students should not shine the light into each other’s eyes.)
2. Have students count the number of mirrors in their homes and chart or graph the results.
3. Bring in silver or silver plated items and observe them tarnish over a period of weeks. At the end of the time, polish one item and compare it with the others. Discuss weather the tarnish harms the strength or usefulness of the items.
4. Using cut flowers or petri dish, demonstrate slowed bacterial growth using Argyrol solution. Teacher can contact a pharmacy for information regarding Argyrol.
5. Bring in several coins if possible minted pre-1964 containing silver, and compare them with coins minted after 1964. 

Measurements/Evaluation:

1. Why is silver used in mirrors?
2. Silver does what to the growth of bacteria?
3. What does tarnishing do to silver?
4. Is pure silver soft or hard?
5. List three uses for silver.

For more information on silver please contact:

The Silver Institute

1112 16^th Street, NW, Suite 240

Washington, D.C. 200036

(202) 835-0185

Or visit their website at www.silverinstitute.org

Silver

Color: White

Weight: Almost 10.5 times as heavy as water

Found: In mineral ores, often mixed with gold, copper or other metals.

Silver is a valuable mineral with many uses. It conducts heat and electricity better than any other metal. It also has the highest reflectivity – this means that when it is polished, light bounces off its surface. The backing of a mirror is an example of this use. Silver is also mixed with chemicals to make photographic paper and film, to make skin creams that help heal burns, and to make compounds that keep cut flowers fresh longer. One reason this works is that silver slows the growth of bacteria.

Silver is soft and easy to shape. It does not corrode except to tarnish, which only makes it look dull or blackened. Tarnishing does not affect a metal’s strength.

Even when people first started writing things down about history, silver was being used for ornaments and utensils. It was also one of the earliest things used for money. In the United States, coins used to be about 90% silver and 10% copper. Because silver is being used faster than it is being mined, the government has changed the way our coins our made. Now, quarters, dimes and half-dollars do not have any silver in them.

Photographic products, films, papers and x-ray products for the medical and dental industries use a third of the world silver demand. Jewelry and silverware represent nearly another third of world silver demand. Some of silver’s other uses are in dental fillings, welding alloys, electrical parts and special airplane parts.