Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

[EX Q]: Limestone is insoluble in water, so acid can dissolve it.
[EX A]: Limestone is insoluble in water, so what can dissolve it?

[EX Q]: The name of film that polyester fibers form is mylar.
[EX A]: What is the name of film that polyester fibers form?

[EX Q]: Salts substances, which are distinct from acids and bases, form when ions form ionic bonds.
[EX A]:
What substances, which are distinct from acids and bases, form when ions form ionic bonds?