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1. Three elements have the electron configurations 1s 2 2s 2 2p 6 3s 2 3p 6 4s 1

ID: 840336 • Letter: 1

Question

1. Three elements have the electron configurations 1s22s22p63s23p64s1, 1s22s22p63s23p5, and 1s22s22p63s1. The first ionization energies of these elements (not in the same order) are 0.496, 1.256, and 0.419 MJ/mol. The atomic radii are 99, 227, and 186 pm. Identify the three elements, and match the appropriate values of ionization energy and atomic radius to each configuration.

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2. Consider the ground state of mercury, Hg.

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3. Which of the following are possible sets of quantum numbers for an electron in an atom? Click the boxes with the correct answers.

(Select all that apply.)

n = 5, l = 2, ml = -2, ms = +1/2

n = 2, l = 0, ms = 0

n = 2, l = 1, ml = 0, ms = 0

n = 7, l = 6, ml = -6, ms = -1/2

n = 7, l = 3, ml = -4, ms = +1/2

Electron Configuration Element Symbol First Ionization Energy (MJ/mol) Atomic Radius (pm) 1s22s22p63s23p64s1 _______________ ________________ _______________ 1s22s22p63s23p5 _______________ _________________

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1s22s22p63s1 ______________ __________________

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Explanation / Answer

1s22s22p63s23p64s1K 0.419MJ 227pm

1s22s22p63s23p5     Cl 1.256 MJ 99pm

1s22s22p63s1   Na 0.496 MJ 186pm

How many electrons have l = 1 as one of their quantum numbers = 3

How many electrons have ml = 0 are = 6

How many electrons have ml = +1 are = 5

possible states:

n = 5, l = 2, ml = -2, ms = +1/2

n = 7, l = 6, ml = -6, ms = -1/2