Reaction of A (green spheres) with B (blue spheres) is shown in the following diagram:
Which equation best describes the reaction?
(a) \(\mathrm{A}_{2}+2 \mathrm{~B} \longrightarrow \mathrm{A}_{2} \mathrm{~B}_{2}\)
(b) \(10 \mathrm{~A}+5 \mathrm{~B}_{2} \longrightarrow 5 \mathrm{~A}_{2} \mathrm{~B}_{2}\)
(c) \(2 \mathrm{~A}+\mathrm{B}_{2} \longrightarrow \mathrm{A}_{2} \mathrm{~B}_{2}\)
(d) \(5 \mathrm{~A}+5 \mathrm{~B}_{2} \longrightarrow 5 \mathrm{~A}_{2} \mathrm{~B}_{2}\)
Text Transcription:
A_2 +2 B arrow right A_2B_2
10 A +5 B_2 arrow right 5 A_2B_2
2 A + B_2 arrow A_2B_2
5 A +5 B_2 arrow right a_2 b_2
Monday Apr. 1: Exam, no notes taken. Exceptions to the Aufbau Principle o Exceptions: electron configurations with 5 or 10 d electrons are preferred over only 4 or 9 o Hund's rule Compares paired and separated electron spins Elements Z=21 through Z=30 have occupied d-orbitals o D orbital drops below s orbital 3d orbital is lower in energy than the 4s Having a half-filled d orbital is more electronically favored than than 4 electrons Electron Configurations & Families of Elements o Groups have similar electron configurations o Noble Gases (group VIIIA) All shells are filled Very unreactive elements Atomic gases Each ending orbital are filled in noble gases o Alkaline Earth Metals (group IIA) 2 electrons in the outer shell 2 Moderately reactive: [filled shell] s Configurations and the Periodic Table o Valence electrons Electrons of the outermost shell of an atom Electrons are "outside" the noble gas core Define chemical reactivity Elements of a group have the same "valence shell configuration" --> similar chemical properties of elements within a group Electron configuration of
