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    Long story short, i've been carrying out a chemistry investigation and at one point I had to vary the concentration of sulphuric acid.

    Which i did by diluting my pur sulphuric acid using the following ratios:

    1:29
    1:19
    1:9
    1:4
    1:3
    1:1



    Now that i'm writing up my investigation I need to convert these ratios into concentrations.

    I would REALLY appreciate if someone could skim through my calculations and confirm whether what I'm doing is the correct way or a load of crap

    NOTE: i'm using 4cm3 of the diluted acid in my experiment.

    Formulas used:
    • Conc = moles/vol
    • moles = mass/RAM
    • mass = volume x density


    Example of my calculation for 1:29 dilution (1 part sulphuric acid, 29 parts water)

    1cm3+29cm3= 30cm3

    (1/30) x 4cm3 = 2/15cm3 (The actual amount of Sulphuric acid in my 4cm3 of diluted solution)

    Next calculating the moles, I need mass first!

    so Mass= (2/15cm3) x 1.84g/cm3 = 0.245
    (NOTE: 1.84G/cm3 is the density of pure sulphuric acid)

    moles now,
    moles = 0.245/98 = 0.0250mol

    Conc:
    0.0250mol/[(2/15cm3)/1000] = 18.7moldm-3
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    Yeah I'm definitely doing something wrong I keep getting 18.7molsdm-3 for all of them :/
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    What was your initial concentration of sulphuric acid?
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    (Original post by joshed)
    What was your initial concentration of sulphuric acid?
    There is no initial conc!
    Its 99% Pure sulphuric acid, I'm making up my own concentrations.
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    Well if it is pure of the pure it is around 18 molar sulphuric acid (I wouldn't spill it :P)

    So your 1/30 dilution would be 18/30 molar solution so a 0.6M solution. (0.6 moldm^-3)
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    (Original post by joshed)
    Well if it is pure of the pure it is around 18 molar sulphuric acid (I wouldn't spill it :P)

    So your 1/30 dilution would be 18/30 molar solution so a 0.6M solution.
    OH!

    Thanks
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    (Original post by Sifr)
    OH!

    Thanks
    Thats ok
 
 
 
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