Hydrogen, rare gases and other non-metals

280410 Hydrogen 280421 Gases, rare; argon 280429 Gases, rare; other than argon 280430 Nitrogen 280440 Oxygen 280450 Boron; tellurium 280461 Silicon; containing by weight not less than 99.99% of silicon 280469 Silicon; containing by weight less than 99.99% of silicon 280470 Phosphorus 280480 Arsenic 280490 Selenium