Copper is one of a group of metals called the coinage metals. How many atoms of copper (Cu) are in a pure copper coin weighing 12.0 g?
the answer is 1.14x10^23
To find the number of atoms in a pure copper coin, we need to use the molar mass of copper and Avogadro's number. Here are the steps:
Step 1: Find the molar mass of copper (Cu).
The molar mass of copper (Cu) is 63.55 g/mol.
Step 2: Calculate the number of moles of copper in the pure copper coin.
Using the given weight of the copper coin (12.0 g) and the molar mass of copper, we can calculate the number of moles:
Number of moles = Mass / Molar mass
Number of moles = 12.0 g / 63.55 g/mol
Step 3: Calculate the number of atoms in the pure copper coin.
To find the number of atoms, we need to multiply the number of moles by Avogadro's number (6.022 x 10^23):
Number of atoms = Number of moles x Avogadro's number
Number of atoms = (12.0 g / 63.55 g/mol) x (6.022 x 10^23 atoms/mol)
Now you just need to perform the calculation in Step 3 to find the number of atoms in the pure copper coin.
To determine the number of atoms of copper (Cu) in a pure copper coin weighing 12.0 g, you will need to follow these steps:
1. Find the molar mass of copper (Cu):
The molar mass of copper can be found on the periodic table, which is 63.55 g/mol.
2. Calculate the number of moles of copper in the coin:
Divide the mass of the copper coin (12.0 g) by the molar mass of copper (63.55 g/mol).
12.0 g / 63.55 g/mol = 0.189 moles of copper.
3. Use Avogadro's number to convert moles to atoms:
Avogadro's number is approximately 6.022 x 10^23 atoms/mol.
Multiply the number of moles of copper by Avogadro's number to find the number of atoms:
0.189 moles x (6.022 x 10^23 atoms/mol) = 1.137 x 10^23 atoms of copper.
Therefore, there are approximately 1.137 x 10^23 atoms of copper in a pure copper coin weighing 12.0 g.
I don't think there are any modern coins that are pure copper. Even the penny, formerly pure Cu consists mostly of Zn now. So forgetting coins, if you want to know the atoms in 12.0 g pure Cu (of anything), that is as follows:
mols Cu = g/atomic mass = 12.0/63.54 = 0.189
1 mol contains 6.02E23 atoms so 0.189 will contain 6.02E23 x 0.189 = ?