Percentage solution

[Tialis]

If you have an X percent solution of a substance dissolved in water, what is the percentage of?

Is it measured by mass or volume of liquid/solid? Can someone give me an example?

 

[chugga chup]

apologies if i've misinterpreted your question...

im of the understanding that if you dissolve a liquid into a liquid, then you express the concentration as %v/v (volume in volume) eg 40% ethanol in water

and if you dissolve a solid into a liquid then you express that as % weight/volume - eg normal saline: Sodium Chloride 0.9% weight/volume

and that this holds true even if you measure a liquid by weight (something viscous like glycerol for instance)

 

[fastandbulbous]

Or put more simply, percentage w/w (weight for weight - applies to most drug solutions) is the nuber of grams per 100ml (which weighs 100g), so 1 percent soln is 1g per 100ml

 

[BilZ0r]

^ what he said...