Most of the countries that issue coins called pennies or cents mint them with an outer layer of copper or bronze (*). Copper oxidizes (i.e. tarnishes) very easily because it reacts with everything from oxygen in the air to dirt and oils on peoples' fingers, so the coins quickly change color in circulation.
(*) Cents and pennies used to be made out of solid copper or bronze, but the cost of copper has gone up so much that nearly every country has changed the coins to be made of a cheaper metal like steel or zinc, with only a thin copper plating so they look the same as they did in the past.
Pennies get dull over time because the copper in the pennies slowly reacts with air to form copper oxide. Pure copper metal is bright and shiny, but the oxide is dull and greenish. When you place the pennies in the vinegar solution, the acetic acid from the vinegar dissolves the copper oxide, leaving behind shiny clean pennies.
At 100 pennies to the dollar, 50,000 pennies makes $500.
dirt
100 pennies makes a Dollar
7000 pennies are in $70.00
copper is important because it makes pennies and pennies are good
Makes sense
Company that makes pennies
it makes pennies
Funny pennies make two dollars
7 quarters = 7*25 = 175 pennies.
Company that makes pennies