Round 1: Tossup 12
High values of this quantity characterize a category of incompatible elements called HFSEs. The dependence of solubility on this quantity explains the cerium and europium anomalies. It’s not concentration, but this quantity is lower for elements in rocks formed from a tholeiitic magma than a calc-alkaline magma. Whether an element with variable values for this quantity partitions into mineral or melt is constrained by the dependence of this quantity on oxygen fugacity. Distinct values of this quantity are held by the iron atoms in magnetite. Since this quantity of the most stable species of calcium and strontium are the same, they substitute each other in minerals. Ferric and ferrous iron differ in, for 10 points, what quantity, the number of electrons added or removed from an element? ■END■
ANSWER: oxidation state [or oxidation number; or redox state; or valence; accept ionic charge; prompt on field strength by asking “high field strength is a consequence of high values of what quantity?”; prompt on oxygen fugacity until read by asking “fugacity controls the value of what quantity that elements take on?”; prompt on speciation; prompt on answers referring to whether an element is oxidized or reduced]
<GC, Other Science> | Packet B - Queens A, UCLA B, Edinburgh B, St. Georges A
= Average correct buzzpoint
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