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    I'm stuck on a few questions
    1)What's so bad about batch processes (other than constant cleaning/labour)
    2)What are the possible products of dehydrating propan-1-ol (is it only propene?)
    3)why does potassium dichromate go from orange to green?
    4)How do you identify Sulfate ions? Name and describe the test
    5) How would you identify a sodium compound? Name and describe the test

    1- batch processes are labour intensive. and slow as well so you get less of the product in a given time, also after you remove a batch, you have to supply energy to get it up to the required operating temperature again e.g. when you're doing metal extraction of titanium
    2- I think it's just propene and water
    3- Acidified (with sulphuric acid) Potassium dichromate is used to test for aldehydes and ketones as it goes green with aldehydes and remains orange with ketones as these can't be further oxidised. I don't think we need to know why they go green but the chromate ions are reduced as the potassium dichromate is an oxidising agent.
    4- Use a solution like barium chloride, something which contains barium ions. First acidify the sample by adding nitric acid, to remove carbonate ions, then add barium chloride and if sulphate ions are present, then barium sulfate forms, a white precipitate. If no sulfate ions present then no observed change.
    5- I don't understand the question haha sorry - maybe you're referring to sodium halides, which form different products inc sulfur containing products when conc sulfuric acid is added
    Hope those above help.


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