An electron has not a corpuscular-wave dualism, but a dualism of an electromagnetic wave and energy, i.e. an electron can be an electromagnetic wave of energy depending on the state. The electrons of one atomic orbital transform tend to fill the entire orbital, evenly distributing space, with a spherical, hemispherical, sectorial-spherical electromagnetic wave according to the principle of minimum total energy, the direction of the molecular orbital depends on the state of the valence electron and is part of the atomic orbital. The electronic formula of the elements at rest and in the excited state has been developed An electron has a single charge, the momentum of which has a closed wave function without interruptions, a discretely equilibrium stationary form of an electromagnetic cloud, and is located in a stationary orbit singly or in pairs in cells with an opposite spin into which the orbital is divided, but in one orbit the cells cannot be arranged in layers, intersect and have various forms, for example, a dumbbell-shaped, ellipsoidal shape. The formation of atomic and molecular orbitals by pairing electron clouds occurs with a high order of electromagnetic waves with transformations. Therefore, we propose a theory of transformation of electron clouds, as an alternative to existing explanations for the formation of equivalent chemical bonds from equivalent electron clouds. A chemical bond always has a single character and is not divided into σ- and π-bonds. For a clear and simple explanation of the theory of transformation of atomic orbitals, you can use schematic projection methods for displaying atomic orbitals, which is in good agreement with the theory of valency.