Question

Ba(OH)2, Ba, Ba3(PO4)2, BaO

Answer 1

Ba(OH)2 - гидроксид бария, основание (щёлочь)

Ba - барий, металл

Ba3(PO4)2 - фосфат бария, средняя соль

BaO - оксид бария, основный оксид

Answer 2

It looks like you've listed a few chemical compounds and elements related to barium (Ba). How can I assist you with these compounds? Are you looking for information about their properties, uses, or something else? Please provide more context or specific questions so I can provide you with the information you're seeking.