Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.
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Question: Question: What is the smallest class of elements? Answer: metalloids

Answer: Metalloids are the smallest class of elements, containing just six elements. They fall between metals and nonmetals in the periodic table.

Question: Question: The modern atomic theory states that all matter is composed of what? Answer: atoms

Answer: The modern atomic theory states that all matter is composed of atoms.

Question: Question: What substance, involved in most biochemical reactions, is essential to life? Answer: water

Answer:
Water is involved in most biochemical reactions. Therefore, water is essential to life.