125s Classroom → 30s Sub-90 Target27-Q Chemistry Mock
Archetype Sub-90 Dry-Wipe Invariant (Subatomic Isoelectronic Ions, Isotopic A_r Weighted Means & Comma Electron Configs (Z ≤ 20)): For two isotopes of mass M1 and M2 with average A_r, use the lever rule: % of M2 = (A_r - M1)/(M2 - M1) * 100%. Isoelectronic species (N³-, O²-, F^-, Ne, Na^+, Mg²+) all share 2,8 (10 e^-).
sub90 ESATARCH-C-01: Subatomic Isoelectronic Ions, Isotopic A_r Weighted Means & Comma Electron Configs (Z ≤ 20)Chemistry
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SUB-90 ZONE (<25S)
0.0s25s Sub-9090s ESAT Budget150s Classroom
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Chemistry•ARCH-C-01•Table-Row Matching
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