The Element Oxygen Was Prepared by Joseph Priestley in 1774 $\rarr$

question 91

Multiple Choice

The element oxygen was prepared by Joseph Priestley in 1774 by heating mercury(II) oxide: HgO(s) $\rarr$ Hg(l) + ¹/₂O₂(g) , $\Delta$ H ^$\circ$ = 90.84 kJ/mol.Estimate the temperature at which this reaction will become spontaneous under standard state conditions.S ^$\circ$ (Hg) = 76.02 J/K·mol
S ^$\circ$ (O₂) = 205.0 J/K·mol
S ^$\circ$ (HgO) = 70.29 J/K·mol

• A) 108 K
• B) 430 K
• C) 620 K
• D) 775 K
• E) 840 K

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Definitions:

Speciation

The evolutionary divergence leading to the formation of new species through mechanisms such as geographic isolation or ecological specialization.

Changes

involve alterations, modifications, or transformations in conditions, situations, or objects over time.

Fusiform Shape

A streamlined, spindle-shaped body design seen in many aquatic animals, reducing water resistance and enabling faster movement.