In 1982, the United States government changed the way it minted pennies. Before 1982, pennies were made of 95% copper and 5% tin. Now they are made of 97.5% zinc coated with copper. Because they weigh different amounts (have different masses) and are still the same item, they make a good model for studying isotopes. 4. What do the two kinds of pennies represent in this exercise?
5. How do the pennies differ? How do isotopes differ?
6. What do the pennies have in common? What do isotopes have in common?

answer

fusion: the energy source of stars. the energy released from the collapse of the gas into a protostar causes the center of the protostar to become extremely hot. when the core is hot enough, nuclear fusion commences. fusion is the process where two hydrogen atoms combine to form a helium atom, releasing energy.

hope it

the answer is the first option

explanation:

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the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

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