Jun 25, 2016
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bootcamp in its explanation said NH3 is a strong base...
last i checked it isn't.. so which is it

this was the text
"
To illustrate this, think of ammonium, NH4+. Ammonium is a weak acid, but the conjugate base of ammonium is ammonia, NH3, which is a strong base.
"


is it..... or what man
 

WheatLom

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pKa of NH3 is 38 so it is quite basic.

pKa of Ammonium about 9-10, so ammonium is pretty acidic.
 

aj30

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pKa of NH3 is 38 so it is quite basic.

pKa of Ammonium about 9-10, so ammonium is pretty acidic.
You're mixing up NH3 with NH2-. The pKa of NH3 is 38 so NH2- is a strong base. The pKa of NH4+ is ~10 so NH3 is a much weaker base than NH2-.
As to OP's question, it's all relative. You're right that NH3 is usually not considered such a strong base (because it's neutral); it's significantly weaker than OH-, for example. However, in the context of that question, it may have been stronger than another base he was talking about so he called it a "strong base".
 

WheatLom

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You're mixing up NH3 with NH2-. The pKa of NH3 is 38 so NH2- is a strong base. The pKa of NH4+ is ~10 so NH3 is a much weaker base than NH2-.
As to OP's question, it's all relative. You're right that NH3 is usually not considered such a strong base (because it's neutral); it's significantly weaker than OH-, for example. However, in the context of that question, it may have been stronger than another base he was talking about so he called it a "strong base".

true, I'm going base off Ochem. but it still chem so it applies.

NH3 would deprotonate compounds with pKa below its pKa.

It is pretty relative. NH3 is a strong base if there was HCl in the solution
 

orgoman22

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bootcamp in its explanation said NH3 is a strong base...
last i checked it isn't.. so which is it

this was the text
"
To illustrate this, think of ammonium, NH4+. Ammonium is a weak acid, but the conjugate base of ammonium is ammonia, NH3, which is a strong base.
"


is it..... or what man
NH3 is a weak base. NH2-, known as the amide ion is a very powerful base. I have been working with this base for over 35 years and it usually finishes the job especially in the E2 process or building larger alkynes during organic synthesis.

Hope this helps

Dr. Romano
 
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