pH Flashcards
If the pH in the blood is too low, what symptoms occur?
Hyperventilation
What is the term If the pH in the bloodstream is too high and what are the symptoms?
Alkalosis, leads to shallow breathing
What is the average charge on a weak acid at its pKa?
-0.5
At what point is a buffer at its most effective?
Around its pKa
What are indicator dyes made from?
Weak acids and conjugate bases, where they are different colours
What indicator varies between Yellow at low pH, green at pH 7.1, and blue at high pH?
Bromothymol blue
Delta G = (related to Ke)
delta G = -RT ln(Ke)
If Ke is bigger than 1 which side will the position of equilibrium be?
Right hand side, favours products
1Calorie =
4218J
What pH range does the citrate buffer go between?
2 - 6
What does Delta G0’ stand for?
0 = standard conditions ' = at pH 7
What does Eh stand for?
Redox potential, E’0/Em7 used for redox potential at pH7
A more negative electrode potential means a…
Better reductant OR better oxidant
Better reductant
More positive electrode potential =
A better oxidant
Delta G0 = (related to potential)
Delta G0 = -n.f.
What is a SHE?
Standard hydrogen electrode
Eh = ….
The actual potential
What makes up a pH meter?
silver chloride electrode, saturated KCl solution, thing glass wall doped with lithium ions
What is the Nernst equation?
Eh = Em + (RT/nF).ln([oxidised][reduced])
Eh = actual potential Em = standard potential
Eh = Em + (RT/nF).ln([oxidised]/[reduced])
What is the name of this equation?
Nernst equation
In a pH meter what is proportional to pH of solution?
The potential difference across the membrane is proportional to pH of solution
What pH range does a succinate buffer cover?
3 - 6.5
What pH range does a phosphate buffer cover?
1 - 3 & 6 - 8
What is the Henderson-Hasselbach equation?
pH = pKa + log([A-]/[HA])
