Electron charge-cloud picture

Most of the carbon atoms in a diamond in a necklace have 6 protons, 6 neutrons, and 6 electrons. The protons and neutrons are in the nucleus, which is surrounded by a cloud of negative charge created by the 6 electrons. You will learn more about the shapes and sizes of different atoms electron clouds in Chapter 11. For now, we will continue to picture the electron-charge clouds of all the atoms as spherical (Figure... 

The intensity of shading at any point represents the magnitude of 1, i.e. the probability of finding the electron at that point. This may also be called a spherical charge-cloud . In helium, with two electrons, the picture is the same, but the two electrons must have opposite spins. These two electrons in helium are in a definite energy level and occupy an orbital in this case an atomic orbital. 

The wave function 9 must satisfy a number of conditions, which arise from the requirement that the function must be physically significant. Here we will only mention that the wave function must be zero at infinity at finite distances 9 will, however, in general be different from zero, that is to say, the charge cloud extends to infinity in contrast to the picture of the electron as a charged sphere. 

In terms of the wave-mechanical picture, an atom may be looked upon as consisting of a positively charged nucleus surrounded by a negatively charged cloud, which is made up of contribution from electrons in various orbitals. Since the centers of positive and negative charges are coincident (see Figure 3.57a), the net dipole moment of the atom is zero. 

Fig. 8.20l The same reasoning is used as in Fig. 8.19, but this time, the key charge distributions are drawn in a realistic way instead of a sehematie diagram. The sections r. = 0 of the two crucial electronic charge distributions are drawn, (a) In the quantum mechanical picture, what decides about chemical bonding is an electron cloud — l n l fc = that contains the charge...

Figure 2.3 I Atoms have often been depicted as resembling a solar system the nucleus is at the center and the electrons orbit around it, as seen here in (a). Although such pictures do help to emphasize the way that protons, neutrons, and electrons are distributed in the atom, they cannot illustrate accurately the currently accepted model of atomic stmcture. Instead, we depict the electrons as clouds of negative charge surrounding the nucleus, as shown in (b). In such picmres, the density of the small dots is related to the probabUity of finding an electron at a particular location.

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