How does ionic strength affect rate of reaction?

The reaction rate increases continuously as the ionic strength increases with alpha-chymotrypsin. With trypsin, the rate increases at low ionic strengths but as the ionic strength further increases a gradual inhibitory effect is observed.

What is the effect of ionic strength?

Ionic strength and tonicity modifiers. Ionic strength can impact the behavior of proteins resulting in salting in (increased solubility) or salting out (decreased solubility). The decrease in solubility with an increase in ionic strength is usually attributed to the colloidal stability of a protein.

What is relation between rate constant and ionic strength?

If one of the reactants is a neutral molecule, ZAZB is zero and the rate constant is expected to be independent of the ionic strength. The rate constant of a reaction between an ion and a neutral molecule should vary with the first power of the ionic strength instead of with the square root.

Does rate constant increase with ionic strength?

For reactions between an ion and an uncharged molecule (Zu = 0), ionic strength should not alter the rate constant. These relationships have been confirmed for solutions that are sufficiently dilute so that the Debye-Hiickel law is applicable (Fig. 5.14).

How does ionic strength effect pKa?

This effect become more pronounced as the ionic strength (or buffer concentration) increases. Therefore, pKa > pKa0, and, in general, the pKa of the buffer increases with increasing buffer concentration, and therefore the pH of a prepared stock buffer solution is decreased on dilution.

How does ionic strength affect buffer pH?

Similarly, an increase in ionic strength will result in a curvilinear increase in pH buffer capacity. Increased ionic strength also results in increased dissolution of sparingly soluble compounds as predicted by thermodynamic theory (Barrow 1966).

What effect does ionic strength have on pH?

On increasing the ionic strength it is observed that the pH optimum moves towards lower pH values when z = – 1 or z = 0, remains the same if z = + 1 and shifts to a higher pH for z = +2.

Why does the solubility of an ionic compound increase as the ionic strength of the solution increases at least up to 0.5 m )?

Explain why the solubility of an ionic compound increases as the ionic strength of the solution increases (at least up to ~0.5 M). As ionic strength increases, the charges of the ionic atmospheres increase and the net ionic attractions decrease.