2025/2026 Exam Questions and Answers
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Zeff increases - 🧠ANSWER ✔✔across the periodic table left to right
Ionization energy increases - 🧠ANSWER ✔✔left to right across a row and
up column of the periodic table
Electron affinity increases - 🧠ANSWER ✔✔left to right across a row and up
a column of the periodic table
Element size increases - 🧠ANSWER ✔✔right to left across and row and
down a column of the periodic table
Ionization energy - 🧠ANSWER ✔✔the energy required to remove an
electron from an atom
, Electron affinity - 🧠ANSWER ✔✔the energy required to add an electron to
an atom
In M.O. theory, the number of atomic orbitals must equal... - 🧠ANSWER
✔✔the number of molecular orbitals
M.O. requirements - 🧠ANSWER ✔✔1. M.O.s must be built from
symmetrically appropriate orbitals
2. Energy in bond pairs needs to be approximately the same
3. Efficient overlap of orbitals in a bond
Anti bonding orbitals - 🧠ANSWER ✔✔higher in energy than bonding
orbitals, created by overlap of orbitals that are out of phase with each other,
contain nodes
Node - 🧠ANSWER ✔✔a region with no electron density
Bond order - 🧠ANSWER ✔✔b=0.5(# bonding electrons - # anti-bonding
electrons)
tells you how many bonds to expect in a molecule
M.O.s for B2, C2, and N2 - 🧠ANSWER ✔✔there is a small change in
energy between 2s and 2p orbitals, causing them to mix