2) Given the following partial (valence-level) electron configurations, (a) identify each element, (b) rank the four elements in order of increasing atomic size, and (c) rank them in order of increasing ionization energy: A B 36 3p 2s 2p c 3p

The atomic number for nitrogen is 7. Which of the following represents the ground state electron configuration for a nitrogen atom? O 1s²2s¹2p4 O 1s²2p5 O 2s²2p5 O 1s²2s²2p³ O 15²25²35³

Rank the following isoelectronic species in order of decreasing size: Argon atom (Ar), Calcium ion (Ca+2), chloride ion (Cl-1), Potassium ion (K+1), Sulfide ion (S-2).

The figure describes the ionization energies (in kJ/mol) for the second-row elements of the periodic table. 2500 2000 1500 1000 500 0 520 Li 899 801 1086 1402 1314 1681 2081 Be B C N O F Ne

Name the element with the atomic orbital diagram shown below:

The first five ionization energies (IE, through IEs) of a Period 6 element have the following patte IE, IE, IE3 IE4 IE5 kJ/mol

A group of students at College of the Canyons conducted an experiment. Two reactors contained different reagents. Reactor 1: sodium metal + argon gas Reactor 2: sodium metal + chlorine gas When the reactor was heated, reactor 1 did not show a chemical reaction between the sodium metal and argon gas. However, reactor 2 showed a vigorous reaction between sodium metal and chlorine gas to form sodium chloride at the same reaction condition. A) Write the electron configurations (noble-gas core notation) each for argon and chlorine atom. Ar: ____________________ Cl: _____________________ B) Explain the difference in the reactivity of the gases with sodium metal. Hint: Use the electron configurations in A).

Which of the following reactions represents an electron gain energy that would be positive (i.e. endothermic). S(g) → S+(g) + e-   Cl(g) → Cl+(g) + e-   Kr(g) + e- → Kr-(g) S(g) + e- → S-(g) Kr(g) → Kr+(g)+ e-   Cl(g) + e- →Cl-(g)

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Arrange the atoms in order of decreasing size: S2-, S, and O-2.