Calculate the [H+] and pH of a 0.0040 M hydrazoic acid solution. Keep in mind that the Ka of hydrazoic acid is 2.20×10−5. Use the method of successive approximations in your calculations or the quadratic formula.

Explanation:

In this, we can with the ionization equation for the hydrazoic acid (). So:

Now, due to the Ka constant value, we have to use the whole equilibrium because this is not a strong acid. So, we have to write the Ka expression:

For each mol of produced we will have 1 mol of . So, we can use "X" for the unknown values and replace in the Ka equation:

Additionally, we have to keep in mind that is a reagent, this means that we will be consumed. We dont know how much acid would be consumed but we can express a subtraction from the initial value, so:

Finally, we can put the ka value and solve for "X":

So, we have a concentration of 0.000285 for . With this in mind, we can calculate the pH value:

I hope it helps!

your parents i think this could be it

smooth muscle is composed of involuntary muscles found within the walls of organs and structures such as the esophagus, stomach, intestines, and blood vessels. those muscles push materials like food or blood through organs. unlike skeletal muscle, smooth muscle can never be under your control.