What has more mass 100 hydrogen atoms 4 sulfur atoms or 1 lanthanum atom?

Answer 1

100 Hydrogen atoms have an atomic mass of 100.794, 4 Sulfur atoms have an atomic mass of 128.26, and 1 Lanthanum atom has an atomic mass of 138.90547.

Answer 2

1 lanthanum atom has more mass than 100 hydrogen atoms and 4 sulfur atoms combined. Lanthanum has a higher Atomic Mass than hydrogen and sulfur, so even though there are more atoms in the other two compounds, the single lanthanum atom is more massive.