Without knowing any equation, you could rule out A (which is dS0).

Gaining more freedom as ions, the entropy goes up, delta S is positive. If you could identify that during dissociation of weak acid molecules, they become ions and gained more kinetic energy, they need to absorb it and thus it's endothermic reaction, delta H is positive. This also explains why increasing T seems to favor the fwd reaction and raise Ka (lower pKa). A pKa/C ratio 0 indicates an endothermic reaction, or that heat can be treated like a reactant. Here we are talking Ka, not Keq, which is fine as they are the same thing, but for specific reactions (Ka, Kb are reserved for acid/base reactions).įor the MCAT you should also remember that as X increases, pX will decrease. Normally we expect heat to raise Keq, and drive reactions forward (though not always). How does the pKa of the reaction change with temperature? In this instance they have given you a ratio of change. The AAMC can make up any ratio it wants, so long as it conforms to the laws of science. Unlike traditional ways of explaining acid-base disorders, this graphic seesaw method is a simple and easy way to achieve understanding.Click to is simply a ratio. The functioning organ can “level the seesaw” by compensating for the dysfunction of the opposite organ to regain homeostasis. When the dysfunction of either the kidneys or lungs causes the seesaw to tip, homeostasis pH is disrupted, causing an acid-base disorder classified as metabolic or respiratory acidosis or alkalosis.

Students developed a working knowledge of how the bicarbonate blood buffer system maintains a physiological pH of 7.4 using a “seesaw” with metabolic on one side, and respiratory PCO 2 on the other at a ratio of 20:1 in the H-H equation. We then used real-world clinical case studies for students to identify acid-base disorders and the appropriate compensatory responses of the lungs and kidneys. We utilized a graphic seesaw model of carbonic acid-bicarbonate equilibrium using the Henderson-Hasselbalch (H-H) equation of a weak acid. Understanding acid-base disorders using weak-acid concepts learned in general chemistry class is challenging for pre-nursing and pre-professional biology students enrolled in anatomy/physiology and biochemistry classes.

Carbonic acid pka