This is my precious thing.

He created a new story.

That's a new thing, isn't it?

There are many things placed in my room.

Acidic oxides react with water to produce acids.

Aluminum is an amphoteric oxide, it reacts with both acids and bases.

Peroxides play an important role in chemical reactions.

I found an old box in the storeroom.

He chose another path.

Basic oxides react with acids to produce salt and water.