Basic Chemical Engineering Knowledge: [One Question per Day] 2011-01-14

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This post was last edited by yunzhongzi112 on 2011-1-13 23:17. Judgment and reasoning question: Generally, basic chemistry uses pH=7 as the threshold for determining the acidity or alkalinity of a solution; therefore, a solution with pH=7 is definitely neutral. ( ) PS:: 1) The top 50 participants will definitely receive a reward, and those who provide a detailed explanation along with the reasons for their choice will earn 1-15 wealth:victory:. 2) Please hide your replies. The method to do this is: http://bbs.hcbbs.com/thread-492556-1-1.html. Do not edit your replies after posting them{:1_90:}, and also avoid copying others’ answers, as that will result in a deduction of points:funk: ； Indicate the question number when answering; otherwise, it will be difficult to determine whether the answer is correct: handshake. 3) The reference answers will be visible once you reply; those who want to confirm their answers may refer to o. 4) Please also avoid submitting answers repeatedly in a malicious manner; if it is due to an operational error, please contact the forum moderators or administrators: call:. Otherwise, points will be deducted. 5) Currently, all the daily questions in the section on basic chemical engineering theories have been compiled; interested users can go and take a look to learn more*. Click directly: Summary post of daily questions in the section on basic theories of chemical engineering (being added). Wrong – it’s not necessarily the case. PH=7 only when the solution is at room temperature of 25. Only in case of C does the solution remain neutral. As the temperature increases, the ion product constant of water, Kw = c(H+) × c(OH−), increases. Therefore, it is greater than 25. At time c, the pH of the neutral solution is 7 (c(H+)) decreases).