Detailed calculations show that the value of Zeff for the outermost electrons in Si and Cl atoms is 4.29 and 6.12 +, respectively. (a) What value do you estimate for Zeff experienced by the outermost electron in both Si and Cl by assuming core electrons contribute 1.00 and valence electrons contribute 0.00 to the screening constant? (b) What values do you estimate for Zeff using Slater's rules? (c) Which approach gives a more accurate estimate of Zeff(d) Which method of approximation more accurately accounts for the steady increase in Zeffthat occurs upon moving left to right across a period? (e) Predict Zeff for a valence electron in P, phosphorus, based on the calculations for Si and Cl.
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- Use the data from Appendix F to graph the variation ofatomic radius with atomic number for the rare-earth elements from lanthanum to lutetium.(a) What is the general trend in these radii? How do you account for it?(b) Which two elements in the series present exceptions to the trend?arrow_forwardThe electron configuration of an element describes how electrons are distributed in its atomic orbitals. (a) Explain the applications of the Aufbau principle, Hund's rule and the Pauli exclusion principle in relation to electronic configuration of oxygen atom. Explain how these principles determine the stability and reactivity of atoms oxygen.arrow_forwardBoron, atomic number 5, occurs naturally as two isotopes, 10B and 11B, with natural abundances of 19.9% and 80.1%, respectively.(a) In what ways do the two isotopes differ from each other? Does the electronic configuration of 10B differ from that of 11B? (b) Drawthe orbital diagram for an atom of 11B. Which electrons are the valence electrons? (c) Indicate three ways in which the 1s electrons inboron differ from its 2s electrons. (d) Elemental boron reacts with fluorine to form BF3, a gas. Write a balanced chemical equation forthe reaction of solid boron with fluorine gas. (e) ΔHf° for BF31g2 is -1135.6 kJ>mol. Calculate the standard enthalpy change in thereaction of boron with fluorine. (f) Will the mass percentage of F be the same in 10BF3 and 11BF3? If not, why is that the case?arrow_forward
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- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning