【简答题】如图是实验室制取气体的装置. (1)仪器X的名称是______. (2)写一个A装置制取O 2 的化学方程式______. (3)B和C装置均可制取CO 2 ,C装置的优点是可随时控制反应的发生和停止.若打开弹簧夹,固体与液体接触,反应便能发生,请简述使C装置中反应停止的原理______. (4)若用D装置采取排水法收集O 2 ,请简述操作步骤______.
【单选题】There is more oil in the Middle East than _______________ of the world.
【简答题】Last summer,I went to Hainan with my family.The 1 was pleasant!The sky was blue,more than I could describe;the sea was blue and bright,more than I could believe. 2 by the sea is just like being in the...
【单选题】Oil refiners can refine a barrel of petroleum so that it yields either more home heating oil or more diesel fuel. If the price of diesel fuel falls, there is
A.
an increase in the supply of home heating oil.
B.
a decrease in the supply of home heating oil.
C.
an increase in the quantity of home heating oil supplied.
D.
a decrease in the quantity of home heating oil supplied.
E.
an increase in the demand for home heating oil.
【简答题】蜡疗的主要治疗方法有 ___________ 、 ____________ 、 _____________ 、 __________ 、 ____________ 等。
【简答题】将下列段落翻译成中文 Bio-diesel is best developed in EU.Its main raw material is colza oil. In 2003, yield of bio-diesel in Europe was more than 1.76 million tons. It is expected that by 2010, the number would ...
【简答题】蜡疗的主要治疗方法有 ___________ 、 ____________ 、 _____________ 、 __________ 、 ____________ 等。