Answer:
A. PO43-
Explanation:
in the given is buffer . so H2PO4- and HPO42- both are present with equal concentration . Na+ is spectator ion it is also present in the concentration higher than the given species above .
but PO4-3 is not present . so it is lowest concentration
Answer: 10L
Explanation:
Given that:
Initial pressure P1 = 1 atm
New pressure P2 = 3 atm
Initial volume V2 = 30 L
New volume V2 = ?
Since pressure and volume are involved, apply the formula for Boyle's law
P1V1 = P2V2
1 atm x 30L = 3 atm x V2
30 atm L = 3 atm x V2
V2 = (30 atm L / 3 atm)
V2 = 10L
Thus, volume changed to 10 liters
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
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