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    3.5g of a mixture of potassium sulphate and potassium carbonate were made up to 250cm^3 of aqueous solution.25cm^3 of this solution required 24.6cm^3 of 0.11M HCL acid to neutrilize.What is the percentage by mass of potassium carbonate in the mixture?
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    Work out how many moles of HCL you used (assuming you know how to do this).
    Write out the balanced equation for the reaction between the base and the acid (are both of K2SO4 and K2CO3 bases? no)
    Work out how many moles there were of the base in 25 cm^3
    Therefore how many moles are there in 250cm^3?
    Once you know the moles and the molar mass, you can find the mass of the solid.
    Then do a percentage

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    (Original post by richpanda)
    Work out how many moles of HCL you used (assuming you know how to do this).
    Write out the balanced equation for the reaction between the base and the acid (are both of K2SO4 and K2CO3 bases? no)
    Work out how many moles there were of the base in 25 cm^3
    Therefore how many moles are there in 250cm^3?
    Once you know the moles and the molar mass, you can find the mass of the solid.
    Then do a percentage
    Thank you,but it says that it is a mixture of K2SO4 and K2CO3.I just did some digging and it says that we should neglect the K2SO4 since it is slightly basic.Thank you anyways
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    (Original post by shady2.0)
    Thank you,but it says that it is a mixture of K2SO4 and K2CO3.I just did some digging and it says that we should neglect the K2SO4 since it is slightly basic.Thank you anyways
    Yes I was aware of that, hence why I told you only one of them is a base.
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    (Original post by shady2.0)
    Thank you,but it says that it is a mixture of K2SO4 and K2CO3.I just did some digging and it says that we should neglect the K2SO4 since it is slightly basic.Thank you anyways
    I doubt very much that (in real terms) potassium sulfate is slightly basic. It is the salt of a strong base and a strong acid and most examination boards will describe it as a neutral salt.
 
 
 
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