Among 10-9 g (each) of the following elements, which one will have the highest number of atoms? Element: Pb, Po, Pr and…
Some Basic Concepts (Mole Concept) · Class 11 · JEE Main Previous Year Question
Among g (each) of the following elements, which one will have the highest number of atoms? Element: Pb, Po, Pr and Pt
- a
Po
- b✓
Pr
- c
Pb
- d
Pt
Pr
🧠 Same mass — lighter atom wins If you fix the mass at , the element with the smallest atomic mass has the most atoms. It is — small means big .
🗺️ Compare the four
- Pb:
- Po:
- Pr:
- Pt:
Praseodymium (Pr) is by far the lightest in this group. So Pr has the highest atom count.
⚠️ Common mistake Many students pick Pt or Pb because the names sound "heavy and metallic". The trick is: same mass, lighter atom = more atoms.
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