For a penny having mass 2.5559g dissolved in hno3 and solving from the process as given in the question we get that the penny has 2.64% of copper (Cu) by mass in it
Mass of penny mp = 2.5559g
concentration of Cu in solution = 1.06 * 10^(-2) mol/L
therefore 100ml diluted solution has
n = 1.06*10^(-2) * 100 / 1000 = 1.06 * 10^(-3) mol of copper
The molecular weight of copper mw = 63.5 g/mol
mass of copper Mcu = n * mw(molecular weight of copper)
⇒Mcu = 1.6 * 10^(-3) mol * 63.5 g/mol
⇒Mcu = 0.06731 g
Percentage by mass of copper in the penny, P= (Mcu/ mp)* 100%
⇒ P = (0.06731/2.5559)* 100 %
⇒P = 2.64%
∴There is 2.64% copper by mass in the penny
Problem to find out the mass percentage of a metal:
brainly.com/question/13767766
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