pH question

[mr chievous]

---

Members don't see this ad.

The pH of the solution that results after mixing 10 mL of 1.0 M HCl and 10 mL of 1.0 M NH3 is the same as the pH of

a. A 0.5 M solution of NH4Cl
b. A 1.0 M solution of NH4Cl
c. A 2.0 M solution of NH4Cl
d. Pure Water

I'm usually good with acid/base questions, but this one has me stumped 😡

 

[LoLCareerGoals]

Treat NH3 like as if it was a "metal".

NH3 + HCL -> [NH4+](aq) + [CL-](aq). Dissolve NH4CL in water and you get the same thing, molarity stays the same.
Answer B.
D is out because [NH4] is weakly acidic and [Cl-] is a nonbase (neutral), so net is weakly acidic.

 

[mr chievous]

Treat NH3 like as if it was a "metal".

NH3 + HCL -> [NH4+](aq) + [CL-](aq). Dissolve NH4CL in water and you get the same thing, molarity stays the same.
Answer B.
D is out because [NH4] is weakly acidic and [Cl-] is a nonbase (neutral), so net is weakly acidic.

The answer is A actually 🙁

 

[justhanging]

The answer is A actually 🙁

Maybe my math is wrong here but don't you have 10 mmol of NH4Cl after the reaction is done? Then divide that by 20 ml and you get a 0.5 M NH4Cl

 

[Captain Sisko]

Maybe my math is wrong here but don't you have 10 mmol of NH4Cl after the reaction is done? Then divide that by 20 ml and you get a 0.5 M NH4Cl

That's what I get, +1