Based on the clue 'compounds featuring this element are used to treat...', what is the answer?

What is referred to by 'composer wolfgang'? Based on the clue 'composers known as the 3 bs', what is the answer? Based on the clue 'composers like haydn mozart established this fren...', what is the answer? Based on the clue 'compost is used as fertilizer this dessert is frui...', what is the answer? Based on the clue 'compounds of this lightest metal have been used to...', what is the answer? Based on the clue 'compressed air cosub2sub or nsub2sub is what prope...', what is the answer? Based on the clue 'comprising 170 islands in 3 main groups this kingd...', what is the answer? Based on the clue 'comprising atum tefnut 7 others the ennead was an...', what is the answer?