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Please help me with this CH6 prac, organics Watch

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    I am currently doing a prac about producing Benzoic acid, white ppt of it from phenyl methanol and this includes all of the buchner funnel method and stuff. Could you PLEASE help me with these questions:

    State why the volume of the solution of the product must be kept to a minimum before crystallising.

    Explain why the solution is cooled in ice at the crystallisation stage.

    Explain why the product benzoic acid is washed before recrystallisation.

    Define the term percentage atom economy and explain why this new concept is useful.

    In a similar experiment, 2.0g of phenylmethanol gave 2.1g of benzoic acid. Explain why this does not mean the yield achieved is over 100%.

    State why the melting point of solid organic compounds are often measured.

    Give one reason why the recorded result could be misleading.

    Tests on benzoic acid:
    1.) Solubility in sodium hydroxide Result:
    1 spatula of benzoic acid dissolves in approx 2cm3 to give colourless solution

    Inference: Guys pls could you also try to help me with this section pls, in the inference according to my teacher, she only said that we must include a symbol equation and give a reason, in terms of chemistry, what gave the result and sort of why....

    2.) Reaction with sodium hydrogen carbonate solution

    Result:
    Effervescence Inference: Reaction with ethanol and concentrated sulphuric acid. Heat about 0.5g of the solid with 1 cm3 of ethanol: add a few drops of concentrated sulphuric acid. Cool and pour carefully into a few cm3 of water in a test tube and note any characteristic colour

    Result: Sweet smell, colourless solution, suggest ester formed

    Inference:
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    (Original post by scaphrax)
    I am currently doing a prac about producing Benzoic acid, white ppt of it from phenyl methanol and this includes all of the buchner funnel method and stuff. Could you PLEASE help me with these questions:

    State why the volume of the solution of the product must be kept to a minimum before crystallising.

    Explain why the solution is cooled in ice at the crystallisation stage.

    Explain why the product benzoic acid is washed before recrystallisation.

    Define the term percentage atom economy and explain why this new concept is useful.

    In a similar experiment, 2.0g of phenylmethanol gave 2.1g of benzoic acid. Explain why this does not mean the yield achieved is over 100%.

    State why the melting point of solid organic compounds are often measured.

    Give one reason why the recorded result could be misleading.

    Tests on benzoic acid:
    1.) Solubility in sodium hydroxide Result:
    1 spatula of benzoic acid dissolves in approx 2cm3 to give colourless solution

    Inference: Guys pls could you also try to help me with this section pls, in the inference according to my teacher, she only said that we must include a symbol equation and give a reason, in terms of chemistry, what gave the result and sort of why....

    2.) Reaction with sodium hydrogen carbonate solution

    Result:
    Effervescence Inference: Reaction with ethanol and concentrated sulphuric acid. Heat about 0.5g of the solid with 1 cm3 of ethanol: add a few drops of concentrated sulphuric acid. Cool and pour carefully into a few cm3 of water in a test tube and note any characteristic colour

    Result: Sweet smell, colourless solution, suggest ester formed

    Inference:
    do you know the answers to questions 1, 2, 5 and 6? Doing the coursework this year (tomorrow actually) and can't find anything online
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    No one did their homework three years ago, I doubt anyone will do yours now.
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    (Original post by Pigster)
    No one did their homework three years ago, I doubt anyone will do yours now.
    I'd thumb this, but it tells me I have to do it to some other people first.
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    There's no need to be like that - there is literally nothing to be found online, i have done my homework thanks
 
 
 
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