When you are given multiple Ka or Kb values (like Ka step one , Ka dos , Ka 3 ), you can also combine them together into an overall Ka or Kb by multiplying them together. The equations below display what I mean.
If Mg(OH) 2 has a Kb 1 of 0.3 and a Kb 2 of 4.5 * 10 -3 what is the over all Kb value?
When the Be(OH)
If H 3 PO 4 has a Ka 1 of 2.8 * 10 -3 and a Ka 2 of 7.1 * 10 -6 . 3 if the overall Ka is 7.75 * 10 -17 ?
Answer: ( 2.8 * 10 -3 ) * ( 7.1 * 10 -6 ) * Ka 3 = 7.75 * 10 -17
If Al(OH) 3 has a Kb 1 of 0.04 and a Kb 2 of 5.1 * 10 -4 what is the over all Kb value?
If H 2 SO 4 has a Ka 1 of 15 and a Ka 2 of 2.0 * 10 -2 . Then what is the over all Ka value?
If H 3 PO 3 has Ka 2 of 4.7 * 10 -5 and a Ka 3 of 2.3 * 10 -8 . 1 if the overall Ka is 5.5 * 10 -16 ?
Answer: Ka1 * (4.7 * 10 -5 ) * (2.3 * 10 -8 ) = 5.5 * 10 -16 — Ka1 = 5.09 * 10 -4
2 has a Kb 1 of 3.6 * 10 -4 and an overall Kb of 8.2 * 10 -12 what would be the Kb 2 ?
Answer: (3.6 * 10 -4 ) * Kb 2 = 8.2 * 10 -12 — Kb 2 = 2.24 * 10 -8
As it happens one to Ka and Kb are regarding one to other inside the a formula. That it formula makes you convert regarding Ka to Kb and you can vise versa. The fresh algorithm try revealed less than .
The great thing about this algorithm is-it as well as permits you in order to anticipate if or not one thing is an acid otherwise a bottom . The way to shape whether or not something is an acidic otherwise legs by simply the Ka or Kb well worth would be to contrast they for the balance ongoing getting liquid as with this new formula below.
Should your Ka turns planning to end up being a bigger matter than simply the fresh Kb then toxins might possibly be an acidic.
If the Kb turns going to become more substantial number than new Ka then your chemical substances might possibly be a base.
Provide the Kb and you may give whether or not the chemical is actually an acid otherwise foot when it keeps a good Ka away from dos.4 * ten -6 .
Answer: Acid (Ka was larger than Kb), Kb = ten -fourteen / 2.4 * ten -6 = 4.17 * ten -nine
Supply the Ka and you can share with whether or not the chemical are an acidic otherwise legs when it have a beneficial Kb off step three.5 * 10 -cuatro .
Answer: Ft (Kb is larger than Ka), Ka = 10 -fourteen / step three.5 * 10 -cuatro = 2.86 * 10 -11
Supply the Kb and you can tell if the toxins are an acid or feet in the event it features a Ka off cuatro.step three * ten -9 .
Answer: Base (Kb try bigger than Ka), Kb = ten -14 / cuatro.3 * ten -9 = dos.thirty two * ten -6
Supply the Ka and tell perhaps the chemical are an acidic otherwise legs when it keeps a great Kb of 8.9 * 10 -11 .
Answer: Acid (Ka is actually larger than Kb), Ka = ten -14 / 8.nine * ten -11 = 1.12 * 10 -4
Give the Kb and you will share with perhaps the chemicals are an acidic or feet in the event it have good Ka out of 7.2 * ten -nine .
Answer: Legs (Kb are bigger than Ka), Kb = 10 -fourteen / 7.dos * 10 -nine = step 1.38 * 10 -6
Supply the Ka and you can tell perhaps the chemical are an acidic or legs if it keeps a great Kb of 4.2 * 10 -twelve .
Answer: Acidic (Ka are larger than Kb), Ka = ten -fourteen / 4.2 
* 10 -11 = 2.38 * 10 -cuatro
Give the Kb and you can tell if the chemicals try an acid otherwise foot if it possess a great Ka out-of 3.4 * 10 -step three .
Then what might function as Ka
Answer: Acidic (Ka is actually bigger than Kb), Kb = ten -fourteen / step 3.4 * ten -3 = 2.94 * ten -a dozen
Supply the Ka and you can give perhaps the chemical compounds is an acidic or feet in the event it possess a beneficial Kb of five.six * ten -eight .
Answer: Legs (Kb was larger than Ka), Ka = ten -fourteen / 5.6 * 10 -eight = step one.78 * 10 -8