【单选题】合成反应开始后,才发现忘记加沸石,该怎么办?
B.
立即停止加热,并等待溶液温度降至室温后,再加入沸石
C.
偶尔忘记加入,没关系,继续实验,应该不会有危险。
【单选题】合成反应开始后,才发现忘记加沸石,该怎么办?
B.
立即停止加热,并等待溶液温度降至室温后,再加入沸石
C.
偶尔忘记加入,没关系,继续实验,应该不会有危险。
【多选题】以下词语读音正确的有()
A.
恫吓dòng 奇葩pā 洞穴xué 祈祷qí
B.
缄口jiān 戏谑xuè 胴体dòng 旗帜zhì
C.
蹇劣jiǎn 细菌jūn 斗殴ōu 霰雪xiàn
D.
僭越jiàn 豆豉chǐ 侥幸jiǎo 香蕈xùn
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【单选题】一个国家要在国际上确立起主权国家的地位,维护国家的尊重和独立,除了要有一定的经济实力以外,还必须具备强大的(),否则就会被动挨打受欺负。
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