A buffer contains significant amounts of ammonia and ammonium chloride.
a. Write an equation showing how this buffer neutralizes added acid (HI).
Here's what I have; where am I going wrong??
NH3+HI---->NH4+ + I-.
b.Write an equation showing how this buffer neutralizes added base (Ba(OH)2)
Again, apparently, I am going wrong; how?
Thanks.
BaOH2+2HCl----->BaCl2+2H2O
Thank you for any help!!!
Chemteam: Thanks but apparently they wanted HI NH3---- NH4I. I am STILL not sure why.
2 Answers
-
Since HI is a strong acid, you could do this:
NH3+H+ ---->NH4+
Neutralizing the base is this reaction:
NH4+ + OH- ---> NH3 + H2O
The reaction you wrote:
Ba(OH)2+2HCl----->BaCl2+2H2O
is that of a strong base (the Ba(OH)2) reacting with a strong acid (the HCl).
Source(s): ChemTeam -
The solution contains NH4+ (ammonium chloride) and NH3 (ammonia). Adding the strong acid HI is adding H+ ions. The H+ ions will react with NH3 to produce more NH4+:
HI + NH3 ----> NH4+ + I-
this reduces the concentration of NH3 and increases the concentration of NH4+ The equation for a basic buffer is pOH = pKb + log[NH4+]/[NH3]. the log term increases, so the pOH increases and the pH decreases.
OH- from Ba(OH)2 reacts with the NH4+ ions in the buffer.
OH- + NH4+ ----> NH3 + H2O
[NH3] increases and [NH4+] decreases, the reverse of above