题干

如图是甲、乙两种物质的溶解度曲线,根据图中信息填空:

(1)t1℃时,甲、乙两种物质的饱和溶液的质量分数____ (选填“相等”或“不相等”).

(2)t2℃时,甲、乙两种物质的溶解度大小关系:甲____ 乙(填“>”、“<”或“=”)

(3)当甲中含有少量乙时,可以用____ 法提纯甲.

(4)要使t1℃时甲的饱和溶液变成不饱和溶液的方法有____ (任填一种即可).

(5)t1℃时,往100g水中加入60g甲,充分搅拌后得到甲的饱和溶液的质量是____ 克.

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答案(点此获取答案解析)

相等,>,降温结晶,升高温度,140

同类题2

   (One day Alice runs after a strange rabbit and comes into a deep hole. She becomes smaller when she wakes up the next day. She finds herself in a wonderland with many amazing things inside.)
   The Caterpillar(毛毛虫) and Alice looked at each other for some time in silence. At last the Caterpillar took the pipe out of its mouth, and said to her in a tired, sleepy voice.
   “Who are YOU?” said the Caterpillar.
   This opening for a talk couldn’t make Alice at ease. Alice replied, rather shyly, “I----I hardly know, sir, just at present ----at least I know who I was when I got up this morning, but I think I must have been changed several times since then.”
   “What do you mean by that?” said the Caterpillar, “Explain yourself!”
   “I can’t explain MYSELF. I’m afraid, sir.” said Alice, “because I’m not myself, you see.”
   “I don’t see.” said the Caterpillar.
   “I’m afraid I can’t put it more clearly.” Alice replied very politely, “for I can’t understand it myself. And being so many different sizes in a day is very puzzling.”
   “It isn’t.” said the Caterpillar.
   “Well, perhaps you haven’t found it so yet.” said Alice. “But when you have to turn into a chrysalis(蛹,茧)----you will some day, you know ----and then after that into a butterfly, I think you’ll feel it a little stranger, won’t you?”
   “Not a bit.” said the Caterpillar.
   “Well, perhaps your feelings may be different.” said Alice. “All I know is, it would make ME feel very strange.”
   “You!” said the Caterpillar scornfully. “Who are YOU?” The question brought them back again to the beginning of the talk. Alice felt a little angry because the Caterpillar was making such VERY short sentences. She drew herself up and said very seriously, “I think you ought to tell me who YOU are first.”
   “Why?” said the Caterpillar.
   Here was another puzzling question. As Alice could not think out any good reason, and as the Caterpillar seemed to be very unpleasant, she turned away.
   “Come back!” the Caterpillar called after her. “I’ve something important to tell you!”
   This certainly gave Alice some hope. Alice turned and came back again.