下列属于新疆的“特色农产品”的是[ ]
A.苹果
B.哈密瓜
C.柑橘
D.玉米
答案:B
设NA为阿伏加德罗常数,则下列说法不正确的是( )
A.在标准状态下,2.24L己烷含有的氢原子数目为1.4NA
B.1.6g甲烷完全燃烧生成二氧化碳和水,转移的电子数为0.8NA
C.14g乙烯和环丙烷混合物中含有的碳原子数目为NA
D.0.1mol乙烷分子中含有的共价键数目为0.7NA
Traffic restrictions have come into effect in Beijing to improve the
capital’s air quality and traffic situation for the 2008 Olympics.
A.in order that
B.in an attempt
C.at an attempt
D.in a try