MathDB

23

Part of 2010 National Chemistry Olympiad

Problems(1)

2010 USNCO Local #23: Spontaneity

Source:

11/25/2012
What are the signs of △H\triangle{H} and △S\triangle{S} for a reaction that is spontaneous only at low temperatures?
<spanclass=′latex−bold′>(A)</span> △H is positive,△S is positive<spanclass=′latex−bold′>(B)</span> △H is positive,△S is negative <span class='latex-bold'>(A)</span>\ \triangle{H} \text{ is positive}, \triangle{S} \text{ is positive} \qquad<span class='latex-bold'>(B)</span>\ \triangle{H}\text{ is positive}, \triangle{S} \text{ is negative} \qquad
<spanclass=′latex−bold′>(C)</span> △H is negative,△S is negative<spanclass=′latex−bold′>(D)</span> △H is negative,△S is positive<span class='latex-bold'>(C)</span>\ \triangle{H} \text{ is negative}, \triangle{S} \text{ is negative} \qquad<span class='latex-bold'>(D)</span>\ \triangle{H} \text{ is negative}, \triangle{S} \text{ is positive} \qquad