Detailed calculations show that the value of Zeff for the outermost electrons in Na and K atoms is 2.51 + and 3.49 +, respectively. (a) What value do you estimate for Zeff experienced by the outermost electron in both Na and K 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) Does either method of approximation account for the gradual increase in Ziff that occurs upon moving down a group? (e) Predict Zeff for the outermost electrons in the Rb atom based on the calculations for Na and K.
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Test Prep Series for AP Chemistry for Chemistry: The Central Science 14th ed AP
- Consider the isoelectronic ions Cl- and K+. (a) Which ionis smaller? (b) Using Equation 7.1 and assuming that coreelectrons contribute 1.00 and valence electrons contributenothing to the screening constant, S, calculate Zeff for thesetwo ions. (c) Repeat this calculation using Slater’s rules toestimate the screening constant, S. (d) For isoelectronic ions,how are effective nuclear charge and ionic radius related?arrow_forward(a) Rank elements: Na, Mg, Al, and K, in increasing order of: (i) atomic size; (ii) ionization energy, and (iii) reactivity. (b) Explain why atomic size decreases from left to right, but increases from top to bottom; (c) Explain why ionization energy increases from left to right, but decreases from top to bottom; (d) Explain why the reactivity of alkali metals (Group-1) increases from top to bottom, where as the reactivity of halogen (Group-17) decreases from top to bottom.arrow_forward22. Valence electrons in an atom of phosphorus are closer to the nucleus than the valence electrons of aluminum because: (A) P has a greater effective nuclear charge and a greater shielding than Al. (B) P has a greater effective nuclear charge with the same shielding as Al. (C) P has the same effective nuclear charge with greater shielding than AI. (D) P has the same effective nuclear charge and the same shielding as Al.arrow_forward
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- On the basis of periodic trends, choose the more metallic element from each pair (if possible).(a) Sn or Te(b) P or Sb(c) Ge or In(d) S or Brarrow_forward3. Which one of each of the following pairs has the higher electron affinity? Explain in detail for each case. (a) C or F (b) F or I (c) Te or I (d) O or S (e) S or Searrow_forward(a) Write the equation representing the 3rd ionization energy for Fe. (b) The electron affinity of In is 29 kJ/mol. Write the equation for which this is the energy change.arrow_forward
- Chemistry: The Molecular ScienceChemistryISBN:9781285199047Author:John W. Moore, Conrad L. StanitskiPublisher:Cengage Learning