How can you tell whether the chemical formula for a compound represents a protein or a carbohydrate?

Hint: A chemical formula is a way of presenting information, using chemical element symbols, numbers, and sometimes also other symbols, about the chemical proportions of atoms which constitute a particular chemical compound or molecule.

Complete answer:
Macromolecules formed by amino acids are proteins. Proteins, polymers of structural units called amino acids, are large-sized molecules. If the chemical formula of a compound contains carbon, hydrogen, oxygen and nitrogen, then it might be a protein. Each amino acid has a carbon atom linked to four groups, which are COOH, $N{{H}_{2}}$, H and a variable group R. A H, \[C{{H}_{3}}\], $C{{H}_{2}}SH$, and many more could be this R. A water molecule is removed from the formula when two amino acids are connected. Several hundred amino acids can be made from a protein. The stoichiometric formula ${{\left( C{{H}_{2}}O \right)}_{n}}$, in which n is the number of carbons in the molecule, can represent carbohydrates. If the chemical formula of the compound contains 1:2:1 ratio of carbon, hydrogen and oxygen, then it is a carbohydrate.

Additional information:
A chemical formula is not a name for a chemical and does not contain words. Although certain simple chemical structures may be implied by a chemical formula. Chemical formulas are able to fully specify the structure of only the simplest of molecules and chemical substances.

Note:
Chemical formulas provide insight into a compound's chemical composition. They also represent the ratios in which to form the compound the constituent elements combine. While representing it in a chemical equation, a compound's chemical formula is crucial. Chemical formulas for the representation of ions, free radicals and other chemical species can also be used.