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If a penny is made of 3. 11 grams of copper, how many atoms of copper are in the penny? show your calculations and answer with unit

User Arviman
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Answer:

Assuming a penny is made of pure copper Cu, then the molar mass of Cu can be used to determine the number of atoms in a penny.

The number of atoms in a mole is the Avogadro constant [math]N_{0}[/math]

The molar mass of Cu is [math]M_{Cu} =[/math] 63.546 grams per mole Cu

How Much Does A Penny Weigh? U.S. pennies since 1982 weigh 2.5 grams or 3.11 grams

Use the Moles to Grams Conversion Formula to solve for moles N[math]_{Cu}[/math]

Choose the mass of a penny to be [math]m_{penny}[/math] = 2.5 g for this question. (Repeat it with [math]m_{penny}[/math] = 3.11 g for yourself.)

Solution:

Find the number of moles of Cu in a penny [math]N_{Cu}[/math]

Find then number of atoms using

Step-by-step explanation:

User Colinmarc
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