 29
29among the abv species only HCO3- can donate H+...
 
			
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1why cannot it be like this : NH3 → H+ + NH2 - ????
then it also donates a proton ??? why can't it be ??
 
			
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1above stat + and accept too. (acid-base action in pairs)
satisfies condn for Bronsted-Lowry Theory
 
			
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1according to arrhenius acid is a substance which furnishes H+ in aq. soln, while bronsted lowry stated that acid is a substance which has tendency to donate proton to another substance.
Now HCO3- satisfies these two while none other do
NH3 accepts proton but not donate them easily, H2 surely can't do any, NH2- can accept proton but doesn't furnish them
 
			
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11Aveek, already Nitrogen has a l.p, so ammonia cannot donate a proton, as Nitrogen becomes highly unstable with a l.p as werll as the electron of a hydrogen atom.
 
			
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106NH3 donates protons. (although quite rare). (as written by aveek)
think of sodamide..
NH3 is (more appropriately a base (not Bronsted base though)).. So It wont be included if single option ..
But multi option.. it is possible