notesonly.in

For 1s, ψ is largest at the nucleus but the radial probability peaks at 0.529 Å. Why no contradiction? Step 1: ψ² (probability density) is max at r = 0. Step 2: But the shell volume at radius r grows as 4πr². Step 3: Radial probability = 4πr²ψ² — zero at nucleus (r=0 kills it), peaks at Bohr radius. Step 4: Both true: densest at centre, most likely found at 0.529 Å. Probability density ≠ radial probability — the classic confusion.