题目内容

在制备乙酰水杨酸时，反应仪器要尽量，以避免。

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制备乙酰水杨酸时，为什么要控制温度不超过90摄氏度，且时间不宜过长？

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Multiple choice questions.1. A cheaper camera is not always ___ to a more expensive one.A. interiorB. inferiorC. exteriorD. superior2. Loneliness can make you feel empty and a sense of _ for someone to really know you.A. askingB. belongingC. longingD. looking3. A strong sense of pride _ over her as she recalled her past glory in her school days.A. weptB. sweptC. criedD. poured4. Patience is _, but its fruit is sweet.A. bitterness B. bitterC. bitteringD. bittered5. It’s important to show that you are open to teammates’ opinions, but it’s also vital that you _ on your own ideas if you believe in them.A. takeB. stickC. fastenD. impose6. No mathematician is _; he may make mistakes, but he must not hedge.A. fallibleB. fallaciousC. falseD. infallible7. He argued with his wife so vehemently that he talked himself _.A. hoarselyB. hoarsenessC. hoarseD. hoarsen8. We are certain that he will _ his illness.A. come overB. go overC. get overD. give over9. Engineering and technology are disciplines _ from one another and from science.A. differB. distinctC. distinctiveD. extinct10. Don't put that cloth over the baby's face, you'll ___ him!A. smotherB. coverC. breatheD. smooth