Final answer:
Non-examples of chemical formulas are symbols or combinations that do not accurately represent the composition of substances, such as individual element symbols or incorrect combinations, rather than proper notations like NaCl, KBr, or H₂O.
Step-by-step explanation:
Chemical formulas represent the types and numbers of atoms that make up a compound. A non-example of a chemical formula might include symbols or expressions that do not accurately reflect the composition of a substance. For instance, writing just 'Na' or 'Cl' would not be a chemical formula, as these are symbols for individual elements, not compounds. Additionally, incorrect or nonsensical combinations such as 'H2' followed by 'Table' would not constitute a valid chemical formula. A chemical formula must represent the actual elements in the compound and their proportions, as in the correct formulas NaCl, KBr, and H₂O. It's essential to understand the difference between monatomic and polyatomic ions in compounds, such as NaCl and Na₂C₂O₄, respectively. It's also crucial to know the order of nonmetals in binary compound formulas and the fact that ionic compounds do not exist as molecules in the solid state, they form a crystal lattice.