gillyr2 said:Homework Statement
A 3.0-g copper penny has a positive charge of 67 mC.
What fraction of its electrons has it lost?
Homework Equations
I don't think I am donig this right. i need guidance
The Attempt at a Solution
i take 3.0 grams * 63.5amu * 6.022 * 10^23 * 29 (electrons) = 3.3*10 ^ 27
67 * 10^-6C / 1.6 * 10 ^ -19C = 4.2 * 10^14
3.3*10 ^ 27/4.2 * 10^14 = WRONG ANSWER. HELP!
gillyr2 said:ok. would this be correct?
3.0 grams / 63.5amu * 6.022 * 10^23 * 29 (electrons) = 8.2 *10^23
67 * 10^-6C / 1.6 * 10 ^ -19C = 4.2 * 10^14
(4.2 * 10^14)/(8.2 * 10^23) = 5.1*10^-10
Is this correct?
To calculate the charge lost from a 3.0-g copper penny, you will need to know the mass of the penny, the number of electrons in copper, and the charge of an electron. The equation for calculating charge lost is: charge lost = (mass of penny / mass of one electron) x (number of electrons in copper) x (charge of one electron).
The mass of a copper penny can vary slightly, but on average, it is approximately 3.0 grams.
There are 29 electrons in one atom of copper. This means there are 29 electrons in one gram of copper.
The charge of an electron is -1.602 x 10^-19 coulombs, which is a unit of electric charge. This means that one electron has a negative charge.
Calculating the charge lost from a copper penny can help us understand the process of oxidation, which is the loss of electrons from a material. It also allows us to quantify the amount of charge lost, which can be useful in various fields such as chemistry and physics.