Question

Pennies today are copper-covered zinc, but older pennies are 3.1 g of solid copper. What are the total positive charge and total negative charge in a solid copper penny that is electrically neutral?

Answer 1

Answer:

$Q_+=1.36*10^5C$

$Q_+=-1.36*10^5C$

Explanation:

From the question we are told that

Mass of old penny $M=3.1g$

Generally the number of moles in a penny is given mathematically as

$n=\frac{M}{A}$

$A=atomic\ number\ of\ copper=>63.5g/mol$

Therefore

$n=\frac{3.1}{63.5}$

$n=0.049mol$

$Avogadro\ Number=(6.023*10^2^3 atom/mol$

Therefore

$N=(6.023*10^2^3 atom/mol *0.049mol$

$N=2.939*10^2^2atoms$

Generally the Total positive charge of the copper is given by

Since its the 29th atom of the periodic table

29 protons

29 electrons

$Q_+=29(2.939*10^22)(1.6*10^1^9)$

$Q_+=1.36*10^5C$

Generally the Total negative charge of the copper is given by

$Q_+=29(2.939*10^22)(-1.6*10^1^9)$

$Q_+=-1.36*10^5C$