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Assume that each atom in a copper wire contributes one free electron. Estimate the numberof free electrons in a cpper wire having a mass of 6.4g (take the atomic weight of copper ot be 64g \({m}{o}{l}^{{-{1}}}.\)


64 grams of copper have 1 mole.
So, 6.4 grams of copper have 0.1 mole
Since 1 atoms contributes 1 electron
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