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    Key points of question:
    • used a measuring cylinder to measure 25cm3 of sulphuric acid
    • added magnesium carbonate to it
    • heated the mixture
    • filter
    • crystallised over the weekend
    • filtered & dried

    Questions I'm struggling with on this experiment:

    b) suggest a reason why gradually mixing in the magnesium carbonate to the sulphuric acid is only possible with a carbonate that is insoluble in water, such as magnesium carbonate

    g) suggest one reason why a student carrying out the preparation apparently obtains a yield over 100%

    I think b) may be so you can see when it stops dissolving, as if it was soluble it would just keep dissolving in it

    and for g) i have no idea... could it be due to the loss in accuracy of the measuring cilinder?
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    bump. pls help if you know, my controlled assesment has to be done tomorrow
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    (Original post by kyraaalm)
    Key points of question:
    • used a measuring cylinder to measure 25cm3 of sulphuric acid
    • added magnesium carbonate to it
    • heated the mixture
    • filter
    • crystallised over the weekend
    • filtered & dried

    Questions I'm struggling with on this experiment:

    b) suggest a reason why gradually mixing in the magnesium carbonate to the sulphuric acid is only possible with a carbonate that is insoluble in water, such as magnesium carbonate
    You add until no more reacts and is observed as a white solid in the solution


    g) suggest one reason why a student carrying out the preparation apparently obtains a yield over 100%
    The product is likely to be still wet ...

    I think b) may be so you can see when it stops dissolving, as if it was soluble it would just keep dissolving in it

    and for g) i have no idea... could it be due to the loss in accuracy of the measuring cilinder?
 
 
 
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