1963 COPPER penny is worth half a billion dollars.
There are 60 seconds in a minute, so a half minute would be 30 seconds. If you have a length of time in half minutes, multiply that by 30 to get seconds. For example, 20 half minutes = 20 x 30 seconds = 600 seconds
You divide the top half by the bottom half example: 3/4= .75
more than a half
Divide it by 70.4202
Phisical
Cutting a piece of copper in half is a physical change because it only alters the physical appearance of the copper without changing its chemical composition.
It is a physical change since...well...no other chemicals are involved...copper is still copper.
Physical change
Physical change
To wire an extension cord, first cut the cord to the desired length. Strip the insulation off the ends of the wires, exposing about half an inch of copper. Twist the exposed copper wires together and secure them with wire nuts. Finally, cover the connections with electrical tape for safety.
Breaking a pencil in half could be an example of physical change, where the pencil's form is altered without changing its chemical composition.
To wire an extension cord properly, first cut the cord to the desired length. Strip the insulation off the ends of the wires, exposing about half an inch of copper. Twist the exposed copper wires together and secure them with wire nuts. Finally, cover the connections with electrical tape and test the cord to ensure it is working safely.
The half equation for the reduction of copper oxide by carbon is: CuO + C -> Cu + CO
If it's one you got in change or a bank roll and is copper-colored on the edge, there is absolutely no silver in it.
Copper and nickel.
Since 1971, U.S. half dollars have been made of nickel-coated copper (91.67% copper and 8.33% nickel).