Question

Pennies today are copper-covered zinc, but older pennies are 3.1 g of solid copper. What is the total positive charge in megacoloumbs (106 C) in a solid copper penny that is electrically neutral? The density of copper is 8900 kg/m^3.

Answer 1

total positive charge in one copper penny is 0.3 MC

Step-by-step explanation:

As we know that the atomic number of copper is

z = 29

now moles of copper present in one copper penny is given as

`n = (3.1)/(29)`

now total number of copper atoms present in it

`N = moles* N_a`

`N = (3.1)/(29)(6.02* 10^(23))`

`N = 6.43* 10^(22)`

Now we know that in one atom there exist 29 protons and 29 electrons

so total positive charge in it

`Q = N(29 e)`

`Q = (6.43* 10^(22))(29)(1.6 *10^(-19))`

`Q = 0.3 MC`