【单选题】Choose the answer that is closest in meaning to the underlined word in the sentence. T he academy holds a highly privileged place in American society because of a long-standing national consensus abou...
【简答题】Each sentence below includes a word that is a synonym of t he underlined word . Write the synonym of the italicized word in the space provided. Fresh garlic may not enhance the breath, but it certainl...
【单选题】()是富有自然美的、情感浓郁的、造型力强的一种线条。
【单选题】The reason for the objection to the use of the word 'law' in modem scientific writing is that ______.
A.
indicates too many commands but few statements of facts
B.
conveys different meanings in human laws and Laws of Nature
C.
is likely to be given wrong interpretations by law-makers
D.
is not clearly defined in modem scientific writing
【简答题】近年来我国的航天事业取得了巨大的成就,在航天发射时,肼(N 2 H 4 )及其衍生物常用作火箭推进剂. (1)液态肼作火箭燃料时,与液态N 2 O 4 混合发生氧化还原反应,已知每1g肼充分反应后生成气态水放出热量为aKJ,试写出该反应的热化学方程式______. (2)在实验室中,用N 2 H 4 ?H 2 O与NaOH颗粒一起蒸馏,收集114~116℃的馏分即为无水肼. ①在蒸馏过程中不需要的...
【简答题】(14分)近年来我国的航天事业取得了巨大的成就,在航天发射时,肼(N 2 H 4 )及其衍生物常用作火箭推进剂。 ⑴液态肼作火箭燃料时,与液态N 2 O 4 混合发生氧化还原反应,已知每1 g肼充分反应后生成气态水放出热量为a KJ,试写出该反应的热化学方程式 。 ⑵在实验室中,用N 2 H 4 ·H 2 O与NaOH颗粒一起蒸馏,收集114~116 ℃的馏分即为无水肼。 ①在蒸馏过程中不需要的仪...
【判断题】Wang Lei’s advice is that Chen Tian does not need to buy any clubs at first because he can rent from the driving range.