[Messi]

Hi guys,

I am going to be titrating ammonia with HCl. Would using methyl red as an indicator be acceptable? Would the end point be indicated by a color change from orange to red? Or yellow to orange? Or yellow to red? I am slightly confused by this.

Thanks!

[Borek]

Calculate pH of equivalence point and compare it with the pH of color change of methyl red.

What is the approximate initial pH? Approximate end pH? Just in terms of acidic/alkaline solutions?

[Messi]

Well, Methyl red is a pH indicator; it is red in pH under 4.4, yellow in pH over 6.2, and orange in between.

Titrating NH3 with HCl, the pH at the equivalence point is 5.24. So I guess the appropriate color change is from Yellow to orange?! Or is Yellow to Red more appropriate?

I would guess Yellow to Red, no?