Answer:
7?
Explanation:
Its somewhat hard to comprehend the question, but if the way I read it was right, its 7.
Answer:
77,007 Pa
Explanation:
Hello!
In this case, since the equivalence statement for atmospheres and pascals is:
1 atm = 101,325 Pa
We can set up the following conversion factor to obtain the pressure in pascals:

Best regards!
Answer:
6.68 X 10^-11
Explanation:
From the second Ka, you can calculate pKa = -log (Ka2) = 6.187
The pH at the second equivalence point (8.181) will be the average of pKa2 and pKa3. So,
8.181 = (6.187 + pKa3) / 2
Solving gives pKa3 = 10.175, and Ka3 = 10^-pKa3 = 6.68 X 10^-11