Question 2.2.1: Consider the elements phosphorus, bromine, sodium, and hydro......

You are asked to describe the composition of some elements.
You are given the identity of the elements.
a. Phosphorus exists in allotropic forms (red phosphorus and white phosphorus). Both contain only phosphorus atoms, but they differ in the arrangement of atoms in the solid.
b. Both bromine (Br_{2}) and hydrogen (H_{2}) exist as diatomic molecules. Hydrogen is a gas under typical room conditions and bromine is a liquid.
c. Sodium exists as individual atoms held together in a metallic lattice.