【简答题】(5分)某化学小组为验证某面包膨松剂由碳酸氢钠和碳酸氢铵两种物质组成,设计如图所示实验(实验开始前弹簧夹都处于关闭状态)。 资料:①面包制作过程中发生化学反应是2NaHCO 3 △ Na 2 CO 3 +H 2 O+CO 2 ↑ NH 4 HCO 3 △ NH 3 ↑+H 2 O+CO 2 ↑ ②氨气极易溶于水,其水溶液称为氨水。 (1)装置C的作用是 。 (2)证明此膨松剂中含有碳酸氢铵的实验操...
【单选题】Which of the following statements is true, according to the speaker?
A.
The speaker made a lot of money when working at the age of 18.
B.
The speaker rode the tide of the technology wave till it broke.
C.
The speaker bad the choice to work as a network administrator.
D.
The speaker took full advantage of his high computer literacy.
【单选题】Which of the following is the best title for the passage?
A.
Never Become Furious at Work
B.
Learn How to Get Rid of Rage
C.
Rage Is Inevitable for Us
D.
Improve Your Bad Temper
【单选题】According to the broadcast, which of the following statements is NOT true?
A.
The plane is landing in 5 minutes.
B.
The flight is boarding at Gate 4.
C.
The number of the Flight is A23.
D.
The destination of the flight is Sydney.
【简答题】某面包膨松剂由碳酸氢钠和碳酸氢铵两种物质组成.化学小组为验证该膨松剂的成分,查阅资料,设计如图所示实验(实验开始前弹簧夹都处于关闭状态). 资料:①膨松剂在面包制作过程中发生化学反应;2NaHCO 3 Na 2 CO 3 +H 2 O+CO 2 ↑; NH 4 HCO 3 NH 3 ↑+H 2 O+CO 2 ↑; ②通常状况下,1体积水溶解700体积氨气,氨气溶于水所得溶液为氨水. (1)是否需要...
【单选题】Which of the following is NOT a reason for the easy raising of the parrot?
B.
Its food is inexpensive.
C.
It does not need a house-sitter.
D.
It does not require daily walks as dogs do.
【单选题】Which word in the following is the best to summarize the sentence, 'Latin people shout a lot. '? ______