Physical vs. Chemistry
What metal was used initially to coat the penny?
Zinc
What two substances were added together in this investigation?
H2O2 and yeast.
Name family 2 - M or NM?
Alkaline Earth, M
Give an example of physical change.
Tearing, ripping, coating.
Before 1982, pennies were made mostly of ______.
Copper.
Colloid.
Name family 17 - M or NM?
Halogens - NM
Give an example of a chemical change.
Gas, change in temperature, sometimes color.
What is the name for the produce where the penny looked like brass?
Alloy
When did gas production occur in the investigation?
After adding the yeast.
Name family 14 - M or NM?
A student mixes acid with a thin metal strip. The metal disappears but a gas is released. Is this a physical or chemical change? Why?
Chemical - gas was not present before we combined the chemicals.
Why do we not make pennies anymore?
Copper became very expensive.
Why is the product called "Elephant Toothpaste?"
It is a great deal of product and very thick, for a large animal!
Name the family in the middle of the table; M or NM?
Transition metals
A student rips up his test. Is this a physical or chemical change?
Physical - the paper itself had not changed.
What is the name of the first chemists? Why?
Alchemists. These scientists understood chemical reactions.
What did we add to the mixture to make it appear more like real toothpaste?
Food coloring.
Name family 18 - M or NM?
Nobel Gases - NM