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2016年高考理综(全国课标卷Ⅰ)的27题以铬元素各种离子的性质和转化为背景,考查了Cr~(3+)的化学性质、CrO_4~(2-)与Cr_2O_7~(2-)的转化反应的离子方程式、溶液的酸碱性对CrO_4~(2-)平衡转化率的影响、反应平衡常数的计算、温度及转化率与焓变的关系、根据Ksp计算离子浓度等知识点。本题满分15分,平均分7.86,难度中等。仔细分析全省的数据统计及一定量的考生答题情况发现,无论哪个层次的考生,都有
In terms of the properties of Cr (3+) ions and the conversion of various ions of chromium ions, 27 subjects in 2016 College Entrance Examination Science (National Course Standard Volume I) examined the chemical properties of Cr 3+, CrO 4 2- and Cr 2 O 7 ~ 2-), the influence of acid and base of the solution on the equilibrium conversion of CrO_4 ~ (2-), the calculation of reaction equilibrium constant, the relationship between temperature and conversion and enthalpy change, the calculation of ion concentration according to Ksp Knowledge point. The full score of 15 points, an average of 7.86, the difficulty of medium. Careful analysis of the province’s data statistics and a certain amount of questions the candidates found that, no matter what level of candidates have