Vrs = ones(1,1000)*-.94;
Press = ones(1,1000)*50;
Temp = ones(1,1000)*9;
Salt = ones(1,1000)*33.86;
k2 = -0.000966638000000000;
Pcoefs = -4.11E-06;
k0 = linspace(lbound,hbound,1000);

[phfree,phtot]= phcalc_jp(Vrs, Press, Temp, Salt, k0, k2, Pcoefs);
phfree(end)-phfree(1)
%%
figure
clf
scatter(k0,phfree)
xlabel('k0')
ylabel('pH free')
title('Vrs: -.94, Pres: 50, Temp: 9, Salt: 33.86, k2: -9.6664E-4, Pcoef: -4.11E-6')