chemynooby2
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31% and 37%
Lets say someone needed 100ml of 37% HCl, but he can only get 31% HCl how much extra HCl needs to be used?
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stoichiometric_steve
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31/37*X
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len1
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37% HCl - strictly speaking % is a ratio, and so dimensionless - you cant get HCl at that strength at RT.
Theres an interesting point regarding the two numbers in the title -
37/32 ~ 1.16 the denisty of concentrated HCl at RT!
Why is this of interest - because some sell 32% HCl and others "a more concetrated version" at 37% - when its actually one and the same thing - H2O
saturated in HCl at RT.
370gms HCl/L
or
320 gms HCl/kg
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Panache
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Quote: Originally posted by len1  | 37% HCl - strictly speaking % is a ratio, and so dimensionless - you cant get HCl at that strength at RT.
Theres an interesting point regarding the two numbers in the title -
37/32 ~ 1.16 the denisty of concentrated HCl at RT!
Why is this of interest - because some sell 32% HCl and others "a more concetrated version" at 37% - when its actually one and the same thing - H2O
saturated in HCl at RT.
370gms HCl/L
or
320 gms HCl/kg |
always wondered about that, Sigma if i recall in Australia used to sell winchesters of 37%, me in my nonesensical wonder always thought it fumed more,
HA!
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chemynooby2
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119.3ml?
Thanks for the info!  Yeah, there are so many scams out there in the chemical
world. 
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Magpie
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| Quote: |
37% HCl - strictly speaking % is a ratio, and so dimensionless - you cant get HCl at that strength at RT
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Len, my lab manual says that concentrated HCl is 12M and is 37.3% HCl by weight.
The single most important condition for a successful synthesis is good mixing - Nicodem
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len1
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Yes Magpie thanks for the correction. Checking the solubility of HCl I found 720gms in 1L H2O or, what amounts to the same thing, at 20C water
absorbs 475 its own volume of HCl gas. That gas weighs 475*36.5/24.1 = 719gms in 1kg of water.
Thats 719/1719 = 42% HCl - something Ive never seen, but is apparently physically possible.
The reason you dont see it is that by definition this HCl of course boils at 20C, and even at 38% it boils at 49C. The stuff of commerce boils at ~
85C and is 32% HCl, or 370gms/L HCl.
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