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

Q: Collision frequency is greater for homogeneous category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'.

A: Collision frequency is greater for what category of catalysts, which also tend to be more sensitive to temperature and more 'expensive'?
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Q: Proteins are long chains of amino acids.

A: What are long chains of amino acids?
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Q: The name of film that polyester fibers form is mylar.

A:
What is the name of film that polyester fibers form?
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