Recall: Phosphorus is an element in which the atoms often bond together in groups of four. What is each group called?An atomA moleculeA latticeAn element

Analyzing the Question

1. Understanding the Terms:

   • "Atom": The basic unit of a chemical element.
   • "Molecule": A group of two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound.
   • "Lattice": A regular arrangement of atoms or molecules in a crystalline structure.
   • "Element": A substance that cannot be broken down into simpler substances by chemical means.

2. Considering Phosphorus: Phosphorus commonly forms molecules consisting of four atoms, which are typically represented by the formula $\text{P}_4$.

Conclusion

The groups of four phosphorus atoms bonded together are specifically referred to as molecules. Therefore, the correct answer is:

Final Answer: A molecule.