题干

某课外小组的同学将玻璃罩内充满纯净的二氧化碳气体,如图A所示,在光照充足的条件下,经过一段时间后.该小组同学用注射器从a处抽取气体,测定玻璃罩内气体的成分及其含量.

【查阅资料】

①植物通过光合作用吸收二氧化碳气体,放出氧气.

②二氧化碳能溶于水,1L水大约能溶解1L二氧化碳气体.

③氢氧化钠和氢氧化钙性质相似,其水溶液都能与二氧化碳发生反应.其中氢氧化钠与二氧化碳反应生成水和碳酸钠,且碳酸钠易溶于水.

【方案设计及实验】采用两种方法测定玻璃罩内气体中氧气的含量.

方法1:用如图B所示的装置测量气体中氧气的含量.

上一题 下一题 0.0难度 选择题 更新时间:2013-09-15 06:13:13

答案(点此获取答案解析)

同类题1

阅读理解

    Our library offers different types of studying places and provides a good studying environment.

Zones

    The library is divided into different zones. The upper floor is a quiet zone with over a thousand places for silent reading, and places where you can sit and work with your own computer. The reading places consist mostly of tables and chairs. The ground floor is the zone where you can talk. Here you can find sofas and armchairs for group work.

Computers

    You can use your own computer to connect to the wi-fi specially prepared for notebook computers; your can also use library computers, which contain the most commonly used applications, such as Microsoft Office. They are situated in the area known as the Experimental Field on the ground floor.

Group-study places

    If you want to discuss freely without disturbing others, you can book a study room or sit at a table on the ground floor. Some study rooms are for 2-3 people and others can hold up to 6-8 people. All rooms are marked on the library maps.

    There are 40 group-study rooms that must be booked via the website. To book, you need an active University account and a valid University card. You can use a room three hours per day, nine hours at most per week.

Storage of Study Material

    The library has lockers for students to store course literature. When you have obtained at least 40 credits(学分), you may rent a locker and pay 400 SEK for a year's rental period.

Rules to be Followed

    Mobile phone conversations are not permitted anywhere in the library. Keep your phone on silent as if you were in a lecture and exit the library if you need to receive calls.

    Please note that food and fruit are forbidden in the library, but you are allowed to have drinks and sweets with you.