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so as seen in the table below, we did our 4 titres plus 1 sighter with Hydrochloric Acid (HCl) (.1M) successfully as the Windex solution with 3 drops of methyl-orange already in, (our indicator) turned to the colour we wanted and were all within .1.

The whole point of this investigation is to measure the concentration of Ammonia in Windex Original Glass Cleaner as a % for the 4 Titres and then of course get an average percentage out of the 4.

However as "Windex" does not have a chemical equation, its not as simple as measuring acetic acid in vinegar as a %, so I dont how to go about my molar/percentage steps.

Did I have all the required information? Or do i need more?

So I am unsure of how to go about finding this? Any info would be great :)Table

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    $\begingroup$ It IS as simple as determining acetic acid in vinegar which does not have "chemical equation" either. You mean chemical formulas, CH3COOH for acetic acid, NH3 for ammonia. For both, you need to involve sample volume. $\endgroup$
    – Poutnik
    Commented Sep 3, 2022 at 5:18
  • $\begingroup$ Please give us the volume of the solution to be titrated by HCl 0.1 M. Without this data, nothing can be done. And what is the meaning of "Sighter" ? $\endgroup$
    – Maurice
    Commented Sep 3, 2022 at 11:36
  • $\begingroup$ You do need to assume that Windex can be approximated as a solution of ammonia in water with nothing else that interferes with the titration. That's probably reasonable. $\endgroup$
    – Andrew
    Commented Sep 3, 2022 at 12:46
  • $\begingroup$ @Maurice I guess the sighter is rough quick shot to have idea about the expected volume. The next fine titrations can go fast until they are approaching the expected volume. $\endgroup$
    – Poutnik
    Commented Sep 3, 2022 at 13:47
  • $\begingroup$ @Maurice, yes sorry, the volume of the windex solution is 20mL or .02L to be titrated by HCl. Sighter is just a rough estimate about the expected volume $\endgroup$
    – Roger
    Commented Sep 4, 2022 at 6:15

2 Answers 2

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Methyl Orange changes color from yellow to red as pH drops from 4.4 to 3.1.

Unless you are titrating a solution with other ingredients that buffer at a higher pH, or react with HCl, your results will be accurate for amonnia.

You can get an MSDS sheet or ingredient list for Windex to make sure.

If any other ingredients interfere with the analysis, purification steps can be done.

With Windex, a chemist might separate the ingredients on a Gas Chromatography column, and test vs a standard solution (of known NH3 concentration) using a detector that works for ammonia.

Another way would be to titrate with a pH meter, rather than an indicator. You will see different pH "plateaus" for different functional groups, such as carboxyl, or phosphate, if they are present.

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Just a few information to help you solve this problem. $\ce{NH3}$ reacts with $\ce{HCl}$ according to :$\ce{NH3 + HCl -> NH4^+ + Cl^-}$. So, your tested solution ($20$ mL) must contain the same amount $\ce{NH3}$ (in moles) as $\ce{HCl}$ from the buret ($\ce{13.5 mL HCl 0.1 M}$). So do calculate this amount of $\ce{HCl}$ (in moles) and divide by $0.02$ L.

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