Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.
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Question: Fact: adding heat to an object sometimes causes chemical reactions

Answer: A chemical reaction may occur when _____ is added to an object.?


Question: Fact: An example of a mixture is clay mixed together

Answer: An example of a mixture is?


Question: Fact: an incandescent light bulb converts electricity into light by sending electricity through a filament

Answer:
Tungsten is a metal which is found in large amounts in filaments, which are used in incandescent light bulbs. These light bulbs work because?