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Which sample contains the most atoms, 1g copper, 1g carbon, or 10g uranium?

User JimSampica
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The number of atoms in a sample can be determined by using Avogadro's number, which states that there are 6.022 × 10^23 atoms in one mole of a substance.

To determine which sample contains the most atoms, we need to compare the number of moles of each substance.

To calculate the number of moles, we can use the formula:

moles = mass (in grams) / molar mass

The molar mass is the mass of one mole of a substance, and it can be found on the periodic table. The molar mass of copper is approximately 63.55 g/mol, carbon is approximately 12.01 g/mol, and uranium is approximately 238.03 g/mol.

Let's calculate the number of moles for each substance:

For 1g of copper:

moles = 1g / 63.55 g/mol = 0.0157 moles

For 1g of carbon:

moles = 1g / 12.01 g/mol = 0.0833 moles

For 10g of uranium:

moles = 10g / 238.03 g/mol = 0.042 moles

Now that we have the number of moles for each substance, we can calculate the number of atoms by multiplying the number of moles by Avogadro's number:

For copper:

atoms = 0.0157 moles * 6.022 × 10^23 atoms/mole = 9.46 × 10^21 atoms

For carbon:

atoms = 0.0833 moles * 6.022 × 10^23 atoms/mole = 5.02 × 10^22 atoms

For uranium:

atoms = 0.042 moles * 6.022 × 10^23 atoms/mole = 2.53 × 10^22 atoms

Therefore, the sample that contains the most atoms is 1g of carbon, which has approximately 5.02 × 10^22 atoms.

I hope this clarifies your question. If you have further questions or concerns, please feel free to ask. :)

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