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So you know the things about outer space like facts that you might not know
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Chemical symbol
This is used to identify an element without having to write the full name and as such is a designation for the element. It is used in chemical reactions and is usually either one or two letters. Some symbols are, Iron - Fe, Hydrogen - H and Oxygen - O.
Valency
This refers to the capacity of an element to combine with another to form a compound. It is measured by the number of electrons that an atom of an element gains, looses or shares when a chemical reaction involving it takes place.
One way you can work out the rate of reaction is by the amount of product that is produced to time. This can also be done with heat and time.
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