Ключевые слова: atmosphere, atomic, atoms, background, biochemistry, blackboard, bond, chalk, chalkboard, chemical, chemistry, composition, compound, concept, decompression, diatomic, dinitrogen, drawing, element, elemental, fertilizer, flat, form, formula, gas, illustration, inert, isolated, line, liquid, model, molecular, molecule, n2, nitrate, nitric, nitrogen, pharma, pharmaceutical, refrigerant, ring, science, scientific, skeletal, structure, style, stylized, wart, writing, written,