Question 2: C adopts exclusion method, A, iron should be burned in oxygen, B, the chemical equation is unbalanced and the reaction conditions are not marked, D, which is sheer nonsense.
The third question: the concept of C. In the displacement reaction, both reactants and products need simple materials, so C is chosen.
Question 4: The general concept of D From the point of view that chemical equations can be balanced, we can know that the element types of reactants and products must be the same (otherwise they are unbalanced), so we choose D. In fact, the conservation of elements in chemical reactions is a default theorem.
Question 5: The activity of element C, the activity of Cu is lower than that of H ion (usually at low concentration) and does not react with it.
Question 6: For the quantitative calculation of C, choose 1 unit of the substance, so the amounts of the substance are mg: 1/24 mol, Zn: 1/65 mol, Fe: 1/56 mol, Al:1/respectively. Then, apart from Al, 1mol of this substance produces 1mol of hydrogen, while 1mol of Al produces 3/2mol of hydrogen, so118 mol of hydrogen is produced from 1/27mol of Al. Finally, the amount of hydrogen generated by aluminum, magnesium, iron and zinc with the same mass:118mol >; 1/24 mol > 1/56mol > 1/65 mol. So C was chosen.
Question 7: The product error of option B is MgO, the product error of option C is ferroferric oxide, and the equation of option D is balanced.
Question 8: C Obviously, at t2, the amount of hydrogen produced is the same. When the equation is balanced, we can know that both iron and zinc are 1mol, and this substance generates 1mol of hydrogen. When the amount of hydrogen is the same, it is obvious that the "amount of substance" consumed by zinc is the same as that of iron, so is there 1mol of Fe =1mol of Zn? Choose C.
Question 9: A chose A at a glance. Iron reacts with sulfuric acid. What's with the water off? Don't worry about ionization, it is far beyond micron, and it doesn't affect the macro quality at all.
Question 10: D In fact, this question means that 0. 1mol of Zn should have generated 0. 1H2, but now the generated H2 is less than 0. 1mol. What fakes are mixed in it? You think, if the metal doped with impurities can produce hydrogen, and its ability to produce hydrogen is stronger than that of Zn, then 0. 1mol of Zn containing impurities will certainly produce more H2 than 0. 1mol. If the doped metal is weaker than that of Zn, then 0. 1mol of Zn containing impurities will definitely produce less than 0. 1mol of H2. The current situation conforms to the second article, so the essence of this problem is that the metal above is weaker than Zn in producing H2. Obviously, D is chosen, and Cu does not react with dilute sulfuric acid at all.