Based upon the value in the heats of formation table on page 555, determine the heat of reaction for the decomposition of rust into iron and oxygen gas. Is this reaction endothermic or exothermic? Explain. 2Fe2O3 4Fe(s) 1 3O2(g)
Effective nuclear charge Explanation of many atomic properties (ionization energy etc.) relies in part on understanding how effective nuclear charge varies throughout the periodic table – there are several ways of calculating Z eff – simple empirical guides, such as Slater’s rules, can provide insight Slater’s rules ▯ Used to estimate effective nuclear charges ▯ [1s][2s2p][3s3p][3d][4s4p][4d][4f][5s5p][5d][5f]... ▯ All electrons to the right contribute 0 to shielding ▯ All electrons in the same group contribute 0.35 to shielding ▯ For s and p electrons, all electrons in the (n-1) shell contribute 0.85 each
