Determine the pH for 100 mL of a 0.4 M solution of acetic acid that has been diluted with 100 mL of water (Ka for acetic acid = 1.74 * 10^-5 M).
Determine the pH when 100 mL of 0.15 M NaOH is added to 250 mL of 0.25 M acetic acid (pKa for acetic acid is 4.76).
What is the free energy cost of pumping calcium ions out of a cell when the cytoplasmic concentration is 0.4 uM, the extracellular concentration is 1.5 mM, and the membrane potential is -60 mV?