Final answer:
Among chlorine (Cl), phosphorus (P), potassium (K), and germanium (Ge), potassium (K) has the largest atomic radius. This is because as we move down a group and from left to right across a period in the Periodic Table, atomic radius generally increases and decreases respectively.
Step-by-step explanation:
Out of the given atoms, namely chlorine (Cl), phosphorus (P), potassium (K), and germanium (Ge), potassium (K) has the largest atomic radius. This is based on the principle that as we move down a group in the Periodic Table, the atomic radius increases. Although germanium (Ge) also lies below silicon and hence has a larger atomic radius as compared to chlorine (Cl) and phosphorus (P), it is smaller than potassium (K) because Ge is located towards the right of K in the Periodic Table. The atomic radius generally decreases as we move from left to right across a period.
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