How many copper, Cu atoms are present in a sample of copper with a mass of 662.4 amu? 42096. 64. 6.277   ××  1024 12. 10.

To find the number of atoms in a sample, you can use Avogadro's number (6.022 x 10^23 atoms/mole) and the atomic mass of the element.

Here are the steps:

1. First, find the molar mass of copper (Cu). The atomic mass of copper is approximately 63.55 amu.

2. Convert the mass of the sample from amu to grams. 1 amu is approximately equal to 1.66 x 10^-24 grams. So, 662.4 amu is approximately equal to 1.1 x 10^-21 grams.

3. Now, convert the mass of the sample to moles using the molar mass of copper. 1 mole of copper is 63.55 grams. So, 1.1 x 10^-21 grams is approximately equal to 1.73 x 10^-23 moles.

4. Finally, find the number of atoms by multiplying the number of moles by Avogadro's number. 1.73 x 10^-23 moles is approximately equal to 1.04 x 10^1 atoms.

So, there are approximately 10 copper atoms in a sample of copper with a mass of 662.4 amu.