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    Have I done it right?



    Succinic acid has the formula (CH2)n(COOH)2 and reacts with dilute sodium hydroxide as follows: (CH2)n(COOH)2 + 2NaOH ? (CH2)n(COONa)2 + 2H2O
    2.0 g of succinic acid were dissolved in water and the solution made up to 250 cm3. This solution was placed in a burette and 18.4 cm3 was required to neutralise 25 cm3 of 0.1 moldm-3 NaOH. Deduce the molecular formula of the acid and hence the value of n.


    My method

    25*0.1/1000=0.0025 which is the moles of NaOH
    0.0025/2=0.00125 which is moles of succinic acid
    18.4cm^3/1000=0.0184dm^3
    0.00125/0.0184= 0.068moldm^3 which is concentration of succinic acid

    2g in 250cm^3 ------> Therefore there is 2g in 0.25dm^3-----> Therefore there is 8gdm^3

    8/0.068=117.65 which is Mr of succinic acid
    Mr of (COOH)2 = 90
    117.65-90=27.65
    27.65/2=1.975 which round to 2

    Therefore n is 2. This is the correct answer just want to check my method. I ahve a test coming up so this is important.

    Greatly appreciated!
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    (Original post by Insanity514)
    Have I done it right?



    Succinic acid has the formula (CH2)n(COOH)2 and reacts with dilute sodium hydroxide as follows: (CH2)n(COOH)2 + 2NaOH ? (CH2)n(COONa)2 + 2H2O
    2.0 g of succinic acid were dissolved in water and the solution made up to 250 cm3. This solution was placed in a burette and 18.4 cm3 was required to neutralise 25 cm3 of 0.1 moldm-3 NaOH. Deduce the molecular formula of the acid and hence the value of n.


    My method

    25*0.1/1000=0.0025 which is the moles of NaOH
    0.0025/2=0.00125 which is moles of succinic acid
    18.4cm^3/1000=0.0184dm^3
    0.00125/0.0184= 0.068moldm^3 which is concentration of succinic acid

    2g in 250cm^3 ------> Therefore there is 2g in 0.25dm^3-----> Therefore there is 8gdm^3

    8/0.068=117.65 which is Mr of succinic acid
    Mr of (COOH)2 = 90
    117.65-90=27.65
    27.65/2=1.975 which round to 2

    Therefore n is 2. This is the correct answer just want to check my method. I ahve a test coming up so this is important.

    Greatly appreciated!
    Yeah it's fine...

    There are a couple of slightly different variations, but they all amount to the same thing.
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    (Original post by charco)
    Yeah it's fine...

    There are a couple of slightly different variations, but they all amount to the same thing.
    Thanks
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    (Original post by charco)
    Yeah it's fine...

    There are a couple of slightly different variations, but they all amount to the same thing.
    could you plz outline how u got the 8gdm3 did u times it by the 2 or sumthing cuz a formula would be appropriate there
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    Oi u mug how did u get 8gdm^3, from 2g of 0.25,
    man will bomb ur yard m8 u get me for displaying insufficient working out to the audience , raah fam watch when man c u slipping on roadz, gon b berr peak and dat.
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    Hey, I'm gonna ask what everyone else is hahaha, how did you get the 8gmdm^3?


    Also would it work if you just multiplied the number of moles of succinic acid by 10? And used that value?
 
 
 
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