Final answer:
Diamond, graphite, AlCl₃, and SiC have sp² hybrid atoms.
Step-by-step explanation:
In the list of species provided, the ones with sp² hybrid atoms are diamond, graphite, AlCl₃, and SiC.
Diamond and graphite are both forms of carbon. In diamond, each carbon atom is bonded to four other carbon atoms in a tetrahedral arrangement, resulting in sp³ hybridization. In graphite, each carbon atom is bonded to only three other carbon atoms, forming layers with sp² hybridization.
AlCl₃ is an example of a molecule that contains a central aluminum atom bonded to three chlorine atoms. The aluminum atom in AlCl₃ has sp² hybridization.
SiC, or silicon carbide, is a compound in which silicon atoms are bonded to carbon atoms. The silicon atom in SiC has sp² hybridization.