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the graph above shows the progress of an enzyme-catalyzed chemical reaction. based on the graph, this enzyme

a. is deactivated in a weakly acidic solution
b. works optimally in a weakly acidic solution
c. is deactivated in a strongly acidic solution
d. works optimally in a strongly acidic solution

A. is deactivated in a weakly acidic solution

Explanation: pH is the measure of acidity or alkalinity.

For acidic solutions the pH ranges from 1 to 6.9, for neutral solutions the pH is 7 and for basic solutions pH ranges from 7.1 to 14.

As pH and are inversely related, more is the concentration of ions, lesser is the pH and vice versa. Thus weakly acidic medium with low concentration of ions have high pH and strongly acidic medium with high concentration of ions have low pH.

As can be seen from the graph, The enzyme works optimally in strongly acidic conditions and is deactivated as the acidity decreases. The enzyme works optimally in strongly basic medium.