o.. density of brine @ 20°C = 1.204 x 0.99820 g/mL = 1.202 g/mL
and finally
.. 250mL brine x (1.202g brine / mL brine) x (0.2641g NaCl / 1g brine) = 79.4g NaCl
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btw.. the LD50 for NaCl = 3000mg/kg oral rat. If that translates directly to humans.. the LD50 for a 50kg person(110lbs) = 150g.
LD50 is the Lethal Dosage that kills 50% of a test population. So drinking a 250mL can of "soup" saturated with NaCl would not be a smart thing to do.