The symbols for the thirteen macronutrient elements in biology spell CHOPKINS CaFe Mg NaCl, or C. Hopkins Cafe [food tastes] m[ighty] g[ood] with salt (NaCl).
The symbols for the thirteen essential nutrients in biology are represented by the acronym CHOPKINS, which can be seen as a clever way to remember the elements CaFeMgNaCl, and is often used to illustrate the importance of salt (NaCl) in food.