why is it safer to eat smaller fish with shorter life spans (salmon) than it is to eat lager fish with longer lifespans (tuna)?

What is a limitation of using a chemical formula, such as c6h1206, to represent a compound? the chemical formula does not show the types of elements that make up the compound. the chemical formula does not show how the atoms are connected to one another the chemical formula does not show the number of atoms of each element in a molecule. the chemical formula does not show the chemical symbols of the elements in the compound