Titration Video – Version 2

Hello everyone! This is my second post on titration, in which you can see the latest version of the video. First, let me remind you briefly what I did last week. I found reliable sources on this technique. Those were the Vogel’s Textbook of Quantitative Inorganic Analysis and Polish National Chemistry Olympiad, which covered both theoretical and practical aspects, respectively. Then I wrote a protocol with the main points that I wanted to include in my video. This was really helpful in organising work in the lab. I made the first video, which I shared with you a week ago. All that is included in my first post.

Post 2The key word for this week of my internship was quality. I was working on improving the video. I basically re-shot all of it a few times, with different camcorders and settings to obtain the best quality. It took a while, but as it is the first video, finding the best device was a crucial task. I think I’ve overcome the technical difficulties quite well and I’m sharing with you the latest version of the video. It has the audio now, and it’s more or less the version I aim for in the end.

So, how does this version differ from the previous one? Very much. Apart from the previously mentioned audio and text, I added the opening, changed the way of showing the apparatus from photos to the camera slowly panning across it. I also improved the overall quality (I hope!).

I want to thank you all for your comments on the previous video – they were invaluably helpful. Again, I need your help with this one – please share your thoughts on this video in terms of mistakes or what I can improve. Feedback on quality, procedure or anything else will be much appreciated. Enjoy watching!

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6 thoughts on “Titration Video – Version 2

  1. I like your video and this is how I would do a titration in real life. However, if being judged against an SQA mark scheme pupils may miss out on a mark if they say fill the burette to zero since the mark scheme has in the past said the level should be “on the scale” and the initial volume recorded. Pupils have been penalised for this in the past.

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      1. I can’t clarify the SQA mean. But I know what has got marks previously and what has not. ” put the meniscus to zero” got no marks. “put the meniscus on the scale” got a mark.

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  2. On the ‘don’t start at zero’ thing I think there’s one argument for starting at zero: in case you forget to take an initial reading. I don’t think it’s a particularly strong argument, but I have seen people make it before.

    There are (at least) a few good reasons to not start at zero. Firstly, the top of the burette is almost always the dirtiest part, particularly the first few mL, so starting lower down helps with volume reading accuracy. Secondly, there is the potential for confirmation bias if you’re looking to start at a particular volume (contrast with starting anywhere within a range and having to read the actual volume accurately each time). Thirdly, apart from the argument in the paragraph above, I don’t think there’s much reason to start at zero. Most titrations don’t use anywhere near the full volume of the burette (and if it is you can alter the sample preparation accordingly).

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    1. Thank you very much Trent. It’s been interesting learning all this (again, or the first time, I’m not sure!). I will use your useful comment as part of the demonstrator notes! I think the confirmation bias is an especially interesting point.

      Thank you,

      Michael

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