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Assume that each atom in a copper wire c...

Assume that each atom in a copper wire contributes one free electron. Estimate the number of free electrons in a copper wire having a mass of 6.4g (take the atomic weight of copper to be 64g `mol^(-1).`

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64 grams of copper have 1 mole.
So, 6.4 grams of copper have 0.1 mole
` No. of atoms in 0.1mole =(6xx10^-23xx0.1) `
` atoms =6xx10^22atoms. `
Since 1 atoms contributes 1 electron
` So 6xx10^22 atoms contributes 6xx10^22 electrons.`
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