问题
选择题
下列试剂能够使Fe2+转化为Fe3+的是（ ）
A．KSCN溶液
B．氢氧化钠溶液
C．氯水
D．铜粉
答案
答案：C
Fe2＋转化为Fe3＋，失去电子，被氧化。因此试剂必须是氧化剂，所以答案是C。
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下列试剂能够使Fe2+转化为Fe3+的是（ ）
A．KSCN溶液
B．氢氧化钠溶液
C．氯水
D．铜粉
答案：C
Fe2＋转化为Fe3＋，失去电子，被氧化。因此试剂必须是氧化剂，所以答案是C。
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| Everyone knows that food is a very important thing for health. If we want to 1 healthy, we should have different kinds of 2 . We need food when we feel 3 . Then, if we 4 a bowl of rice or a piece of bread, we do not feel hungry. We should have enough food. But do we eat the right kind of food? Bread is good for us. It helps us 5 . It 6 keep us warm when the weather is cold. Meat, fish, eggs and milk 7 all very good for us. They help us to grow. They keep us 8 . We must have some of these kinds of food every day. We should have breakfast, then go to 9 . We also need fruit and 10 . These also help us to grow and keep fit. | ||||
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