问题 选择题

表中原子化热、晶格能、键能的单位都是kJ·mol-1

金属金属原子化热离子化合物晶格能共价键键能
Na108.4NaCl786Cl-Cl243
Mg146.4NaBr747Si-Si176
Al326.4MgO3791Si-Cl360
则下列说法正确的是

A.Na(s)与Cl2(g)反应生成1molNaCl(s)放出的热量为556.1kJ

B.Si(s)+2Cl2(g)=SiCl4(g)  △H= - 602kJ·mol-1

C.从表中可以看出,氯化钠的熔点比晶体硅高

D.从表中数据可以看出,微粒半径越大金属键、离子键的越弱,而共价键却越强

答案

答案:B

题目分析:A不正确,因为晶格能是在反应时1mol离子化合物中的阴阳离子从相互分离的气态结合成离子晶体时所放出的能量,因此生成物氯化钠应为气态;反应热就是断键吸收的能量和形成化学键所放出的能量的差值,所以根据键能计算可知,B正确;氯化钠是离子化合物,其熔点比晶体硅低,C错误;微粒半径越大共价键越弱,D错误。

单项选择题 B1型题
单项选择题

(B)

My father was chief engineer of a merchant ship, which was sunk in Word War Ⅱ, The book Night of the U-boats told the story.

Memories

In September, 1940, my mother, sister and I went to Swansea, where my father’s ship was getting ready to sail. We brought him a family photograph to be kept with him at all times and keep him sale.

Then I remember my mother lying face down, sobbing. She had heard from a friend that the ship had been sunk by a torpedo(鱼雷).

I can remember the arrival of the telegram (电报), which in those days always brought had news. My grandmother opened it. It read, "Safe. Love Ted."

My most vivid memory is being woken and brought down to sit on my father’s knee, his arm in a bandage.

He was judged unfit to return to ea and took a shore job in Glasgow for the rest of the war. For as long as I can remember, he had a weak heart. Mother said it was caused by the torpedoes. He said it was because of the cigarettes, whichever, he died suddenly in his early 50s.

Ten years later I read Night of the U-bouts and was able to complete the story.

Torpedo

One torpedo struck the ship; Father was in the engine room, where the third engineer was killed. He shut down the engines to slow the ship making it easier for it to be abandoned.

By the time he got on desk (甲板) he was alone. Every lifeboat was gone except one which had stuck fast. When he tried to cut it free, it swung against the ship, injuring his hand and arm. He had no choice but to jump—still with the photograph in his pocket.

Three days later, he and other survivors were safe in Glasgow. All 23 with him signed the back of the photograph.

A Toast

In my room is the book and the photograph. Often, glass in hand; I have wondered how I would have dealt with an explosion, a sinking ship, a jump into a vast ocean and a wait for rescue Lest(以免)we forget, I have some more whisky and toast the heroes of the war.

We can infer that the mother and children went to Swansea()

A. to meet a friend

B. to see the father off

C. to take a family photo

D. to enjoy the sailing of the ship