Why does the waste acid produced in the nitration of benzene (68% of it) have a freezing point as low as around 0 degrees after being concentrated to about 88%?
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This post was last edited by swwsdwf on 2009-11-18 at 23:09. Why does the sulfuric acid (waste acid) produced in the nitration of benzene, which is about 68% concentrated, have an increased freezing point after being concentrated to around 88% – it freezes at almost 0 degrees, right? (The original statement that the freezing point is \"very low\" is incorrect.) Isn’t it said that the freezing point is around -30 to -40 degrees Celsius?
The freezing point of sulfuric acid changes with its concentration. At concentrations ranging from 0 to 100% by weight, there are several minimum freezing points: 1) At a concentration of 38%, the freezing point is –72.2 degrees; 2) At a concentration of 73.5%, the freezing point is –42.5 degrees; 3) At a concentration of 93.77%, the freezing point is –34.86 degrees; 4) At a concentration of 100%, the freezing point is 10.37 degrees; 5) At a concentration of 98%, the freezing point is –0.7 degrees. Please refer to http://bbs.hcbbs.com/redirect.php?tid=125247&goto=lastpost. I have corrected your question – please let me know if it is appropriate The reason why the waste acid (about 88%) solidifies at around 0 degrees is that the waste acid produced by you contains other substances as well, and it is the interaction between these solutes that causes this phenomenon