Download
Close
Автор:
id:
Ключевые слова:
affinity, atom, atomic, background, capsule, chemical, chemistry, configuration, education, electron, element, f, fluorine, gas, groups, halogen, illustration, laboratory, mass, material, mendeleev, metal, molecule, number, periodic, periods, physics, properties, proton, red, school, science, scientific, sign, square, structure, substance, symbol, table, weight, white,