Quantum Mechanics - Quick integral probability question

AI Thread Summary
The discussion centers on the probability of locating an electron in hydrogen energy levels using quantum mechanics. The user questions why the probability density expression for a volume element does not include the radial component dr in the first integral. They also seek clarification on the absence of integral limits for dr in the second expression. The confusion arises from the distinction between the probability density and the volume element in spherical coordinates. Ultimately, the user is looking for a clearer understanding of these quantum mechanics concepts.
binbagsss
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Okay so my book says (the context is electron hydrogen energy levels) the probability of finding the electron within dv=dv(r,∅,θ) is :

ψψ*r^2sinθdθd∅ [1]

where ψ is the wavefunction

And to find within dr of r is : ∫∫ψψ*r^2sinθdrdθd∅,[2] where the inner integral ranges over 0 to PI and the outter from 0 to 2PI

I don't really understand this. Why doesn't the first integral [1] for dv not require dr? As isn't the volume element given by r^2sinθdrdθd∅?

I also don't really understand why we don't need to include some integral limits corresponding to dr in [2]

If anyone can help explain things this would be greatly appreciated . Ta in advance !
 
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Looks like a typo to me.
 
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