Ka vs. Kb

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505095972
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Ka vs. Kb

Postby 505095972 » Fri Jan 18, 2019 9:53 am

Can someone help explain when you use Ka, Kb, or Kc? Are Ka and Kb used whenever H30+ or OH- is a product?

Chem_Mod
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Re: Ka vs. Kb

Postby Chem_Mod » Fri Jan 18, 2019 9:59 am

Ka and Kb are used for acid and base respectively, usually dealing with the dissociation process in water. Kc is the equalibrium concentration and is used widely used in different reactions.

Julia Lee
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Re: Ka vs. Kb

Postby Julia Lee » Fri Jan 18, 2019 10:06 am

Ka times Kb= Kw = (10^-14)
pKa +pKb = 14

lukezhang2C
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Re: Ka vs. Kb

Postby lukezhang2C » Fri Jan 18, 2019 11:03 am

Ka and Kb are just used for acid/base dissociation, and Kc is just the equilibrium concentration.

Philipp_V_Dis1K
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Re: Ka vs. Kb

Postby Philipp_V_Dis1K » Fri Jan 18, 2019 11:12 am

K is the letter that denotes an equilibrium reactions quotient, the c is just denoting it's a non-acid /base reaction, a for acid, b for base.

204929947
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Joined: Fri Apr 06, 2018 11:03 am

Re: Ka vs. Kb

Postby 204929947 » Fri Jan 18, 2019 8:05 pm

PKw= POH+PH
PKa+PKb=14
PKa refers to acidity acid and PKb to weak basicity base

Xinyi Zeng 4C
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Re: Ka vs. Kb

Postby Xinyi Zeng 4C » Fri Jan 18, 2019 8:33 pm

Just to add on, Ka and Kb are used for weak acids and bases only, as strong acids and bases will fully dissolve.

Niveda_B_3I
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Re: Ka vs. Kb

Postby Niveda_B_3I » Sat Jan 19, 2019 5:16 pm

Ka time Kb is Kw, and pKa + pKb is 14, and also equal to pKw

Katelyn Phan 2A
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Re: Ka vs. Kb

Postby Katelyn Phan 2A » Sat Jan 19, 2019 5:52 pm

Ka is used for acids and Kb is used for bases. You can also determine the Ka based on knowing the Kb and vice versa.

Celine Hoh 2L
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Re: Ka vs. Kb

Postby Celine Hoh 2L » Sat Jan 19, 2019 9:08 pm

And Kp is the pressure constant?

MadelynNguyen1F
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Joined: Fri Apr 06, 2018 11:04 am

Re: Ka vs. Kb

Postby MadelynNguyen1F » Sat Jan 19, 2019 9:50 pm

Yes Kp is the equilibrium constant expressed in terms of partial pressures of gases

chrisavalos-2L
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Re: Ka vs. Kb

Postby chrisavalos-2L » Sat Jan 19, 2019 11:14 pm

Ka is used when dealing with a chemical reaction that includes an acid and Kb is used when there is a chemical reaction that includes a base. Kc is the equilibrium constant of concentrations.

lukezhang2C
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Joined: Fri Sep 28, 2018 12:18 am

Re: Ka vs. Kb

Postby lukezhang2C » Sun Mar 17, 2019 3:41 pm

Ka is the ionisation constant, used when dealing with acids and excess protons in a solution. Kb is typically used with bases, and finding the pOH of a solution. Kc is just the relation of Ka and Kb which is Ka X Kb = 10^-14


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