Question #abda4 Chemistry The Periodic Table Periodic Trends in Atomic Size 1 Answer Dee Dec 12, 2016 #Cl^-# Explanation: #Cl^-# would be larger because it's an anion which gains one more electron than its original outer shell of the neutral Cl atom. Answer link Related questions Why do periodic trends exist for electronegativity? Why does atomic size increase down a group? What do periodic trends of reactivity occur with the halogens? How can I determine atomic size of ions? The atomic radii of transition metals do not decrease significantly across a row. As you add... How does the octet rule affect periodic trends? How does the number of protons relate to atomic size? How does the periodic trend of atomic radius relate to the addition of electrons? How does atomic size affect the energy released during bonding? How does atomic size affect reactivity? See all questions in Periodic Trends in Atomic Size Impact of this question 2337 views around the world You can reuse this answer Creative Commons License