By expressing your answer in a chemical formula you are defining the composition a class of compounds. Paraffin hydrocarbons, for example, are made up of carbon and hydrogen. The number of hydrogen atoms is always two. You can use either method to answer the question. Use the correct state markers to write your answer. The wrong state marker will penalize your submission. Incorrect markers include a blank fraction or a stacked sub/superscript.
The chemical formula will contain the elements that make up a molecular and their proportions. To represent each atom, you will use chemical symbol symbols. The subscript will indicate the number of elements in the compound. Subscripts are only used when more than 1 element is present. Chemical formulas can also be abbreviations for compound names. However, if your answer is more complex than that, you will have to use the full chemical structural formula.
There are two types of chemical formulas. The molecular and the structural. The molecular formula describes the number of atoms in a single molecule. The empirical formula calculates the simplest whole-number of atoms. Structural formulas indicate the bonding arrangement of atoms within the compound. This is called isomerism, which is due to the arrangement of the atoms.