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    Calculate the amount ot Triethanol (Molecular weight = 149.19) required to make 500mls of a 200mM solution.

    I don't even know where to start!
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    (Original post by ChemEng90)
    Calculate the amount ot Triethanol (Molecular weight = 149.19) required to make 500mls of a 200mM solution.

    I don't even know where to start!
    mol of solid = mass in g / molar mass in g per mol

    mol of solutions = concentration in mol per dm cube x volume in dm cube

    Find mol of the solution you want to make, then equate with mol of solid, find the mass of solid required in g. Though I imagine, triethanol is probably liquid?
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    ...Rep to anyone who can works this out. I'm baffled!!!
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    Work out how many moles you need

    500 mL/0.5 dm3 and 200 x 10-3 mol dm-3

    concentration = moles/volume
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    (Original post by EierVonSatan)
    Work out how many moles you need

    500 mL/0.5 dm3 and 200 mol dm-3

    concentration = moles/volume
    Rewrite the second line please, it's not clear mate. It's partly coming back to me now lol.
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    hmm, elementary chemist
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    This isn't for me, it's for a friend lol. I don't do Chemistry, nor have time for it lol.
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    I've been trying to edit that post for 15 minutes

    :lol: fixed
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    ....scratch that LIE. Retardation and tiredness set in.
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    Thanks EierVonSatan and shengoc. I'll rep you both.
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    The term 'Molecular weight' threw me off completely, cos I'm used to seeing molecular mass.
 
 
 
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