What is the difference between valence and core electrons, and how do they relate to atomic properties such as bonding and reactivity? (keywords: shielding) Explain in DETAIL (3-4 sentences).

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4.) The dissociation energy of a carbon-bromine bond is typically about 276 KJ/mol. What is the maximum wavelength of photons that cause C---- Br bonds dissociation? and which kind of electromagnetic radiation--ultraviolet, visible, or infrared--does the wavelength you calculated correspond to? Group of answer choices A) 435 nm; Blue visible light B) 570 nm; Green/yellow visible light C) 7.2 x 10-31 m; gamma rays D) 435 nm; Red visible light

2-98 Explain how the ionization energy of atoms changes when proceeding down a group of the Periodic Table and explain why this change occurs.