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    I'm really stuck on this question, can I have some guidance please?


    Vandium(IV) chloride, VCl4, is a brown liquid which behaves as a lewis acid. It dissolves in hexane without reaction, but reacts violently with water to form a blue solution of oxovandium(IV) ions according to the equation:

    VCl4 + 3H2O = VO^(2+) + 2H3O^(+) + 4Cl^(-)

    In order to determine the percentage of vanadium in a given sample of VCl4, a weighed sample was added to an excess of water. The chloride ions were removed by precipitation and filtration, and the solution of vanadium(IV) was titrated with standard potassium manganate(VII).

    A 0.475g sample of VCl4 required 24.1cm3 of 0.0200M KMnO4 for complete reaction. In the titration, the reaction occurring is the oxidation of vanadium(IV) to vanadium(V).


    Calculate the percentage of vanadium in the sample analysed.


    I have found out the number of moles of KmnO4 and VCl4, but I am not sure what i have to next?
    Can anyone help?

    Thanks!
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    (Original post by starstudent7)
    I'm really stuck on this question, can I have some guidance please?


    Vandium(IV) chloride, VCl4, is a brown liquid which behaves as a lewis acid. It dissolves in hexane without reaction, but reacts violently with water to form a blue solution of oxovandium(IV) ions according to the equation:

    VCl4 + 3H2O = VO^(2+) + 2H3O^(+) + 4Cl^(-)

    In order to determine the percentage of vanadium in a given sample of VCl4, a weighed sample was added to an excess of water. The chloride ions were removed by precipitation and filtration, and the solution of vanadium(IV) was titrated with standard potassium manganate(VII).

    A 0.475g sample of VCl4 required 24.1cm3 of 0.0200M KMnO4 for complete reaction. In the titration, the reaction occurring is the oxidation of vanadium(IV) to vanadium(V).


    Calculate the percentage of vanadium in the sample analysed.


    I have found out the number of moles of KmnO4 and VCl4, but I am not sure what i have to next?
    Can anyone help?

    Thanks!
    You have to construct the balanced equation for the reaction between V(IV) and MnO4- ions
 
 
 
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