用NA表示阿伏加德罗常数的值。下列叙述中不正确的是______ A.分子总数为NA的

题型:单项选择题

问题:

用NA表示阿伏加德罗常数的值。下列叙述中不正确的是______

A.分子总数为NA的NO2和CO2混合气体中含有的氧原子数为2NA
B.28g乙烯和环丁烷(C4H8)的混合气体中含有的碳原子数为2NA
C.常温常压下,92g的NO2和N2O4混合气体含有的原子数为6NA
D.常温常压下,22.4L氯气与足量镁粉充分反应,转移的电子数为2NA

考点:教师招聘考试中学教师招聘笔试教师公开招聘考试中学化学
题型:单项选择题

阅读理解。

     My hometown is Tianjin.  It is one of the biggest cities in China. It is next to Beijing-the capital of

China. So people say, Tianjin is the eastern gate of Beijing. Bohai Bay is in the southeast of Tianjin.  It is

famous for the Haihe River which runs through the city.  There are eighteen districts (区)  in Tianjin.

Heping District is the center. It's the busiest district in Tianjin. Binhai New District is in Tanggu. There are many big foreign companies there.  It is a beautful district.  Jixian is in the north of Tianjin.  It is famous

for the Great Wall. Thousands of people visit it on holidays. Farmers there are very kind and friendly.

You can buy some fruit and nuts (坚果) there. They are very fresh.

     Welcome to Tianjin ! Welcome to my hometown !

1. The writer was born in ________.

A. Beijing          

B. Bohai Bay

C. Tianjin          

D. Nanjing

2. Tianjin is on the ________of Beijing.

A. south        

B. east

C. northwest    

D. southeast

3.  ________ is the busiest one in Tianjin.

A. Heping District    

B. Binhai New District

C. Jixian District      

D. Bohai Bay

4. The ________ runs through the city.

A. Bohai          

B. Tongding River

C. Haihe River      

D. Changjiang River

5. Jixian is famous for ________.

A. the Great Wall      

B. the Bohai Bay

C. Haihe River        

D. the foreign companies

题型:单项选择题

下列有关使用胶头滴管的说法中不正确的是[ ]

A.胶头滴管主要用于取少量液体

B.使用时先挤压胶头,再伸入溶液中吸取

C.洗涤胶头滴管时可取下胶头冲洗

D.使用过程中将胶头滴管平放在桌上

题型:单项选择题

设计一个网站,必须先定位好网站的()。

题型:单项选择题

水冲洗时,管道内应有足够的流量,水冲洗流速一般不小于()。

A、3m/s

B、2.5m/s

C、2m/s

D、1.5m/s

题型:单项选择题

一个信息系统的战略应当表达出企业的【 】的需求

更多题库