The indicator propyl red has a Ka of 3.3 X 10-6 . It is red at low pH and yellow at higher pH. What is the approximate pH range over which it changes color

4.48 - 6.48

Explanation:

A pH indicator works in a better way in a range of pH = pKa ± 1. That means we need to determine the pKa of the indicator propyl red to find the range over which it change its color. That is:

pKa = -log Ka

pKa = -log 3.3x10⁻⁶

pKa = 5.48

That means the range over propyl red will change from yellow to red or vice versa is:

4.48 - 6.48

hurricanes form when warm, moist air from the ocean surface quickly rises into the atmosphere and forms storm clouds and rain. when the clouds are formed, heat is released which warms the cool air in the upper regions of the atmosphere so that the cycle can continue. which two phases of the water cycle are repeated in this process?