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96年高考化学试题总的来说是好的。下面谈一下本人对23题的疑问。原题:120℃时,1体积某烃和4体积O_2混和,完全燃烧后恢复到原来温度和压强,体积不变,该烃分子式中所含的碳原子数不可能是(A)1;(B)2;(C)3;(D)4[试题答案选(D)] 疑问1:题中给出120℃,但没有给出压强,那么水是什么状态呢?根据大学无机化学中水的相图的知识,水的临界温度是374℃,临界压力是218大气压,就是说当温度高于374℃时,无论加多大压强也不能得到液态水,而只有气态水,但是本题只给出120℃,其状态就不一定是气态,压强大到一定程度可能成为液态。而出题者显然以为该温度下水是气态的,因此不给出压强是不严密的。
The 96-year college entrance examination chemistry test is generally good. Let me talk about my own question about the 23 questions. The original title: At 120°C, 1 volume of certain hydrocarbons and 4 volumes of O 2 are mixed and restored to original temperature and pressure after complete combustion. The volume remains the same. The number of carbon atoms contained in this hydrocarbon formula cannot be (A) 1; ( B) 2; (C) 3; (D) 4 [question answer (D)] Question 1: The question gives 120 °C, but no pressure is given, then what is the state of the water? According to the university’s inorganic chemistry, water The knowledge of the phase diagram shows that the critical temperature of water is 374°C, and the critical pressure is 218 atmospheres. That is, when the temperature is higher than 374°C, no liquid water can be obtained no matter how much pressure is added, but only the gaseous water, but this problem is only given. At 120°C, the state is not necessarily gaseous, and the pressure is so strong that it may become liquid. The subject apparently thought that water was gaseous at this temperature, so it was not rigorous to give pressure.