Here's how to calculate the moles of carbon atoms in 3 grams of carbon:

1. Molar Mass of Carbon:

* The molar mass of carbon is 12.011 g/mol. This means that one mole of carbon atoms weighs 12.011 grams.

2. Conversion:

* To find the number of moles in 3 grams of carbon, we use the following formula:

* moles = mass / molar mass

* Plugging in the values:

* moles = 3 g / 12.011 g/mol

* moles ≈ 0.25 mol

Therefore, there are approximately 0.25 moles of carbon atoms in 3 grams of carbon.