1. Understanding Moles and Atomic Mass
* Mole: A mole is a unit of measurement that represents a specific number of particles (atoms, molecules, etc.). One mole contains 6.022 x 10^23 particles (Avogadro's number).
* Atomic Mass: The atomic mass of an element is the average mass of its atoms, expressed in atomic mass units (amu). You can find atomic mass on the periodic table.
2. Calculating Mass
* Lead (Pb): The atomic mass of lead is approximately 207.2 amu. Since we have 2 atoms of lead, the total mass would be:
2 atoms Pb * 207.2 amu/atom Pb = 414.4 amu
* Helium (He): The atomic mass of helium is approximately 4.00 amu. To find the mass of 5.1 x 10^-23 moles of helium, we'll use the following steps:
* Calculate the number of helium atoms:
5.1 x 10^-23 moles He * (6.022 x 10^23 atoms He/mole He) = 3.07 atoms He
* Calculate the total mass:
3.07 atoms He * 4.00 amu/atom He = 12.28 amu
3. Comparison
* 2 atoms of lead have a mass of 414.4 amu.
* 5.1 x 10^-23 moles of helium have a mass of 12.28 amu.
Therefore, 2 atoms of lead have a greater mass than 5.1 x 10^-23 moles of helium.
