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The 2011-2012 academic year, the second semester of the second semester examination
Relative atomic mass: C 12 O 16 Fe 56 Cu 64
7. The following substances are liquid at normal temperature and are insoluble in organic matter with a higher density than water. (A) Benzene B. C. monochloromethane Acetic acid D. Bromobenzene 8. In the following statement, what is incorrect is () ① different nuclides of the same element are called isotopes.
② Chemical bonds can combine ions and atoms. ③ The essence of metal corrosion is the process in which metal atoms lose electrons and are reduced.
④Ksp is not only related to the nature and temperature of the poorly soluble electrolyte, but also to the ion concentration in the solution ⑤During the discharge of the battery, the mass of the anode decreases and the mass of the anode increases ⑥Al and Fe can react with certain oxides under certain conditions ⑦Dry ice and ammonia are weak electrolytes⑧The main components of gasoline and peanut oil are fats
A. ①③④⑦⑧ B. ②③④⑤⑧ C. ③④⑤⑦⑧ D. ①③⑤⑥⑦ 9. The solubility curves of KNO3 and NaCl are shown in the figure on the right. The following statement is correct
A. Dissolve 35 g of NaCl in 100 g of water at 40 ° C. When the temperature is reduced to 0 ° C, crystals can be precipitated.
B. B. Solute mass fraction of saturated KNO3 solution at 20 ℃ ＞ 31.6% C. A. The amount of KNO3 and NaCl solution are equal. Solid KNO3 is mixed with NaCl, which can be purified by recrystallization
10. The nuclear charge number of an element X is less than 18, the number of electron layers of its atom is n, the number of outermost electrons is 2n + 1, and the endoplasm of the atomic nucleus
The number of children is 2n2-1. In the following statements about X, what is incorrect is (). ． ． A. X can form a base of the chemical formula X (OH) 3. X can form an oxo-sodium salt of the chemical formula NaXO3. The number of outermost electrons and nuclear charges of X atom cannot be even D. X can form compounds with certain metallic or non-metallic elements
11. The following groups of ions cannot coexist due to redox reactions (). ．
A. H +, Fe2 +, Cr2O72-, SO42-
B. Al3 +, Na +, SO42-, HCO3-
C. Na +, Cu2 +, Cl-, S2-D. Fe3 +, K +, SCN-, Cl-
12. The relationship between the amount and concentration of the particles in the following solution is correct ()
A. After mixing the two solutions of sodium acetate and hydrochloric acid at normal temperature, the solution is neutral, then in the mixed solution: