Not by a single one. You can have the individual compounds making up the mixture be present in a stoichiometric ratio, of course, though you don't have to.
French dressing does not have a chemical formula because it is not a chemical. It is a mixture made of different components like vinegar, olive oil, etc. that have their own chemical formulas.
See this link.
This is a mixture not a compound with a chemical formula.
Dishsoap is a mixture and so does not have a chemical formula.
Obsidian is volcanic glass, a mixture and as such has no chemical formula.
Toothpaste is a mixture, not a compound and so there cannot be a chemical formula.
There is no chemical formula for a mixture. Water has a chemical formula, soft drink, milk, yogurt, wood does not. Rust has a chemical formula, however, yogurt, ice cream, pancakes have a recipe - no chemical formula.It is a mixture, not a compound
A crouton is a mixture of a ton of things, and therefore does not have a chemical formula.
Cheetos is a food, a mixture of products and chemical compounds - no chemical formula of cheetos.
A vaccine is not a chemical compound it is a mixture.
There is no chemical formula for the product soybean oil. This is because soybean oil is not a chemical but a mixture.
H2SO4W3FE5O6SO3 + nitrous oxide = Arizona ice tea