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    When you mix two immiscible components together ( let's say toluene and water ) you get two layers. Toluene stays in the upper layer

    Whereas another immiscibility example of dichloromethane or ether in water again shows that these two compounds tend to stay in the lower level.

    I am just wondering what is the principle of such distribution.
    It is not the molecular weight because all of the given examples of mine have RMM > RMM of H2O.



    SoO.. I have a hunch that it is to do with the viscosity and the hydrophobicity??
    The more viscous and more chained the compound.. the better it floats thus stays in the upper level and vice versa. Example petrol stays on top of water due to long linear chains of aliphatic carbon atoms...



    Would anyone agree on that? Have I identified the reason ? )

    sorry 'bout such a litany
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    You are trying to be too clever . It's simply down to density. The more dense liquid sinks to the bottom and the less dense one floats on top.

    Toluene floats on top of water because it is less dense that water. Dichloromethane sinks to the bottom because it's more dense than water. You said ether is in the lower level but (assuming you mean diethyl ether) it floats on top because it is less dense that water.

    A general rule is that chlorinated solvents are more dense than water but the others are less dense.
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    I might have overcomplicated things. Thanks for such a concise answer. :] Everything seems to add up.. I was doing a practical which actually showed that diethyl ether sinks So maybe there might have been some bias , because based on density - you're totally right.

    (Original post by Kyri)
    You are trying to be too clever . It's simply down to density. The more dense liquid sinks to the bottom and the less dense one floats on top.

    Toluene floats on top of water because it is less dense that water. Dichloromethane sinks to the bottom because it's more dense than water. You said ether is in the lower level but (assuming you mean diethyl ether) it floats on top because it is less dense that water.

    A general rule is that chlorinated solvents are more dense than water but the others are less dense.
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    (Original post by oZu)
    I might have overcomplicated things. Thanks for such a concise answer. :] Everything seems to add up.. I was doing a practical which actually showed that diethyl ether sinks So maybe there might have been some bias , because based on density - you're totally right.
    You may have overcomplicated things but you were thinking like a scientist which was cool .

    In this experiment of yours, did you add pure diethyl ether and pure water (doesn't matter if it was distilled water or not) together? Because in that case, I guarantee you diethyl ether would be on top. Some possibilities are:

    You accidentally added some other solvent which is more dense than water.

    You made a mistake in identifying the organic layer.

    They gave you something else which was labelled diethyl ether by mistake.

    The ether had something dissolved in it which made it more dense than water. I've never seen this but I've heard it can happen in rare cases since dissolving stuff in a solvent changes its density but not usually by a huge amount.
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    (Original post by Kyri)
    You may have overcomplicated things but you were thinking like a scientist which was cool .

    In this experiment of yours, did you add pure diethyl ether and pure water (doesn't matter if it was distilled water or not) together? Because in that case, I guarantee you diethyl ether would be on top. Some possibilities are:

    You accidentally added some other solvent which is more dense than water.

    You made a mistake in identifying the organic layer.

    They gave you something else which was labelled diethyl ether by mistake.

    The ether had something dissolved in it which made it more dense than water. I've never seen this but I've heard it can happen in rare cases since dissolving stuff in a solvent changes its density but not usually by a huge amount.
    This. Pretty much spot on.
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    Well you must have identified all of the scenarios :] well done and yeah.. it must have been one of them

    again cheers.. and what great people seem to come around these parts of TSR ;]
 
 
 
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