[Jman]

I'm a bit confused about calculating the W/W % of Hydrochloric acid. On the 1L bottle it says 280mlHCL. Does this mean its 28% or higher W/W?
I'm not sure because of the difference between ml & grams if any. On calculating the W/W it says how many grams is added for the total volume. I'm not sure if 280ml is close to 280grams.

Thanks

[Borek]

280 mL is a volume, not concentration.

You can't calculate the mass without knowing the density, which is a function of concentration. 1 g/mL is probably not far from th ereality, but you can be off by even close to 20% for really concentrated stuff.

[Arkcon]

280mls of what?  Like Borek: said this makes a difference.  Ok, zo you're reading a label of HCl, so they measured out 280mls of HCl, a gas, and stirred it into some water?  It's silly to assume that would work like I just described.  Now, if you bubble HCl into water, until the water can take no more, that's approx 35%, and that what industry tends to work with.