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HELP I dunno what happened in my prac (1 Viewer)

fatassmcfat

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Ok I had a normal prac lesson (not assessed) on indicators. We just got hydrochloric acid and diluted different levels of it. Im confused about two things
1) If you keep on diluting acid, will it just make like an exponential graph but never reach 7 (neutral)? And vice versa for base (can only come very close to 7, but not actually on it?)
2) I used phenolphtelein and the results showed the first 5 tubes (AKA most concentrated ones) were dark pink, and the next 7 became clear. Shoudnt it be other way around? (lol I think we maybe used a base o_O). Also, the first 1st tube was dark pink at the start, but after a few minutes it became completely clear randomly. Why did that happen?

THANK YAR
 

someth1ng

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Ok I had a normal prac lesson (not assessed) on indicators. We just got hydrochloric acid and diluted different levels of it. Im confused about two things
1) If you keep on diluting acid, will it just make like an exponential graph but never reach 7 (neutral)? And vice versa for base (can only come very close to 7, but not actually on it?)
2) I used phenolphtelein and the results showed the first 5 tubes (AKA most concentrated ones) were dark pink, and the next 7 became clear. Shoudnt it be other way around? (lol I think we maybe used a base o_O). Also, the first 1st tube was dark pink at the start, but after a few minutes it became completely clear randomly. Why did that happen?

THANK YAR
You need to be clearer on what you exactly did and how you diluted. For example, did you add say 3 drops of indicator at the start then continually diluted the solution or did you start with the acid, took a sample then diluted (and so on) and added 3 drops of indicator to each sample.
 

fatassmcfat

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I had a test tube of concentrated acid in test tube 1, then took 1 ml of that acid and put it test tube 2and filled it with 9 ml water, then took 1 ml of acid from test tube 2 and put it in test tube 3 and filled with 9 ml water etc. (so test tube one ph is 1 cause its concentrated/strong acid, and theoretically test tube 2 is ph2 (it was increased by tenfold dilution) and test tube 2 is ph3 etc)
 

fatassmcfat

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Once i finish preparing all my solutions i added 2-3 drops indicator in all
 

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