What information does a chemical formula of a compound provide?
a. the type and amount of elements
b. the different kinds of compounds included within the chemical formula
c. the types of molecules present in a formula
d. the correct amounts of substances to mix together to make a formula

I think the best option is A. A chemical formula of a compound provides information on the type and amounts of elements in that compound. For instance, we have NaOH. From the given formula, we see that it contains the elements sodium, oxygen and hydrogen. Also, their corresponding number of molecules.

Because a model would make the investigation easier to understand

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