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    Hey,

    Would anyone be able to have a look at these questions, and explain how you get to the answers? Thanks in advance.


    1. This question concerns the preparation of 1-bromobutane from butan-1-ol, 50% sulfuric acid and sodium bromide. The mixture was placed in a flask and heated under reflux for ten minutes.

    Boiling temperature / °C
    1-bromobutane 100
    butan-1-ol 118

    (a) The reason that 50% sulfuric acid was used rather than concentrated sulfuric acid is because concentrated sulfuric acid

    A would oxidise some of the bromide ions to bromine.
    B would cause the reaction to go too fast.
    C would react with the bromide ions to produce hydrogen bromide.
    D is too hazardous a chemical.

    (b) The reaction mixture was distilled. The impure distillate did not contain

    A butan-1-ol
    B 1-bromobutane
    C sodium bromide
    D hydrogen bromide

    (c) The impure 1-bromobutane was washed with concentrated hydrochloric acid and shaken in a tap funnel with a base to remove acidic impurities. Which of the following would remove acidic impurities without reacting with the 1-bromobutane?

    A calcium hydroxide solution
    B sodium hydroxide solution
    C calcium chloride solution
    D sodium hydrogencarbonate solution

    (d) The 1-bromobutane was washed with water, dried and distilled. Which of the following is the correct procedure?

    A heat the liquid to 118 °C and collect the substance given off
    B heat the liquid to 100 °C and collect the substance given off
    C boil the liquid and collect the fraction that boils off between 116 and
    120 °C
    D boil the liquid and collect the fraction that boils off between 98 and
    102 °C
 
 
 
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