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    can anyone say whether this statement is true or false?

    "When you have 1 litre of water and you dissolve 300 grams of salt, the volume of the resulting solution is less than 1 litre"


    :rolleyes: Cheers.
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    Why would it be less? You're adding mass. Maybe it's some magic Chemistry, as I don't do Chem, but basic common sense tells me it's false. =O
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    I don't know. But I wouldn't think so. You could easily test that though .. It isn't the mass that's important, when you dissolve sodium chloride in water it forms hydrated ions. Where the water molecules surround the sodium and chloride ions. It is the volume that is occupied by these hydrated ions compared to the water molecules on their own which will give you the change in volume.
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    Sorry not too sure either, although I don't think it is quite as easy as just because you're adding something the volume increases. The mass would increase but due to the way the water molecules bond and surround to the salt ions perhaps volume does decrease if it becomes more compact?

    Interested to know the actual answer though.
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    There will be a small increase in volume for adding NaCl there are some salts that will decrease the volume of water though - it's all to do with how the ions affect the bulk structure of water (complicated!).

    If you look up the density of salt water for different concentrations (e.g. 20% w/w = 1.152g/mL) and work out the volume using density = mass/volume you'll see that a 20% NaCl(aq) solution has more volume than a pure water solution (though not a big difference)
 
 
 
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