These resources are frequently used as a self-check tool to verify their own calculations and logic.

The by N.E. Kuznetsova and A.N. Levkin is a widely used Russian educational resource designed to complement standard chemistry curricula with a focus on problem-solving. It is typically part of the "Ventana-Graf" (now part of Prosveshcheniye) educational series, intended for both basic and advanced study levels. Core Components and Content

Finding mass, volume, or molar ratios in chemical reactions.

Exercises on the theory of chemical structure, hybridization, and chemical bonding in organic molecules.