Electron cloud and Quantum Physics Is it possible to detect the Electron Cloud? Also, it it possible for the Electron Cloud itself to contain any mass?
 A: It's always a danger to assign classical meaning to quantum objects, like electron clouds. One way to help clarify what's happening in atoms is to compare it with a another bound system: the nucleon.
Can we detect the quark-cloud in a proton? Yes, by elastic electron scattering. The angular/energy dependence cross section becomes the Fourier transformation of the charge density. This is as much a detection of the quark cloud as is Rayleigh scattering of weather radar from a rain drop a detection of the rain drop.
This has been done with electrons scattering off of bound atomic electrons:
"Collisional breakup in a quantum system of three charged particles," by T.N. Rescigno, M. Baertschy, W.A. Isaacs, and C.W. McCurdy appears in Science magazine, 24 December 1999. (https://www2.lbl.gov/Science-Articles/Archive/quantum-scattering.html)
whence the follow plot is taken:

What we see here is a prediction of what the electron cloud looks like from the paper (via angular dependence), and actual data, which qualifies (for me) as "seeing the electron cloud". 
A: The electron cloud is just a simplified and somewhat inaccurate way to describe electron orbitals around the atom. The electron cloud is not a physical thing, it's just something to convey the idea that the electrons do not exist at any point in space at some point in time. Rather, there is a probability of detecting an electron at a certain position in space. It is this idea of probability that the electron cloud is trying to capture. It is also used to contrast earlier models of the atom where the electrons existed in orbitals at fixed distances from the nucleus.
Therefore, there is no way to detect an electron cloud, and it certainly doesn't have any mass.
