We want to find how much charge is on the electrons in a nickel coin. Follow this method. A nickel coin has a mass of about 5.7 g.
a. Find the number of atoms in a nickel coin. Each mole (6.02 × 10^23 atoms) has a mass of about 57.9 g. Answer in units of atoms.
b. Find the number of electrons in the coin. Each nickel atom has 28 electrons/atom. Answer in units of electrons.
c. Find the magnitude of the charge of all these electrons. Answer in units of C.
a. To find the number of atoms in a nickel coin, we need to calculate the number of moles first and then convert it into atoms.
Step 1: Calculate the number of moles in a nickel coin.
Given mass of the nickel coin = 5.7 g
Mass of one mole of nickel atoms = 57.9 g
Number of moles = (mass of the nickel coin) / (mass of one mole of nickel atoms)
= 5.7 g / 57.9 g
b. To find the number of electrons in the coin, we need to multiply the number of atoms by the number of electrons per atom.
Step 2: Calculate the number of atoms in the nickel coin.
Number of atoms = (number of moles) x (Avogadro's number)
= (number of moles) x (6.02 × 10^23)
Step 3: Calculate the number of electrons in the coin.
Number of electrons = (number of atoms) x (number of electrons per atom)
= (number of atoms) x 28 electrons/atom
c. To find the magnitude of the charge of all these electrons, we need to multiply the number of electrons by the charge of one electron.
Step 4: Calculate the magnitude of the charge of all the electrons.
Magnitude of charge = (number of electrons) x (charge of one electron)
Note: The charge of one electron is approximately -1.6 × 10^-19 C.
Remember to use the units consistently throughout the calculations.
Now you can plug in the numbers and solve the equations to find the answers.