（1）通常所说的化石燃料是指______．我国东海和南海的海底有_爱下问搜题

搜题请搜索小程序“爱下问搜题”

问题填空题

（1）通常所说的化石燃料是指______．

我国东海和南海的海底有大量“可燃冰”，它是甲烷分子居于水分子形成的笼中的产物（如图所示），“可燃冰”是否属于化石燃料？______．

（2）甲烷在0的海水中，只要压强达到3Mpa就能形成“可燃冰”．已知海底每增加10m，压强就增大0.1Mpa，在这一温度下，多深的海底可能找到“可燃冰”？______．

（3）在“可燃冰”中，平均每46个水分子构成8个笼，每个笼里容纳1个CH₄分子或1个游离的H₂O分子．若这8个笼中有6个笼容纳的是CH₄分子，另外2个笼容纳的是H₂O分子，则“可燃冰”的平均组成是下列各项中的______．

A．CH₄-2H₂O B．CH₄-6H₂O C．CH₄-8H₂O D．CH₄-10H₂O．

答案

（1）煤、石油和天然气是常见的三大化石燃料，“可燃冰”的成分是甲烷，属于化石燃料．

故答案为：煤；石油；天然气；属于化石燃料．

（2）根据题意可知，当压强达到3Mpa时，

3Mpa

0.1Mpa

×10m=300m．

故答案为：300m深度以下．

（3）由平均每46个水分子构成8个笼，每个笼里容纳1个CH₄分子或1个游离的H₂O分子，可知笼中共有6个甲烷分子和2个水分子，这8个笼中共有6个甲烷分子和48个水分子，所以“可燃冰”的平均组成CH₄?8H₂O．

故答案为：C．

选择题

下列关于物理事实、物理原理或物理方法的说法正确的是（）

A．开普勒发现了万有引力定律，人们尊称他为“天体的立法者”

B．伽利略发现单摆的等时性，并推导出单摆的公式

C．超高压带电作业的工人穿戴的工作服中包含金属丝，是为了静电屏蔽

D．从电容器的电容表达式可以看出，与成正比，与成反比

完形填空

Having said goodbye to his parents, Alvin, with his wife and one-year-old son, set off back home． 16 excited, Alvin and Clare talked and laughed happily． And even little Alax 17 from time to time． The family were   18 from trip．
But about three hours later things began to   19 ． It was starting to snow． Alvin sped up the car,   20 to arrive home before dark． But it was too dangerous to drive fast now． Because it was snowing more and more heavily． So Alvin had to   21 down． The snow on the  22 was getting deeper and deeper until it was hard to   23 on it． Their car slipped (滑落) off the way and got stuck in the deep snow   24 the engine refused to start again．
“The snow doesn’t seem to   25 ． Shall we stay in the car waiting to be frozen to death or walk ahead through the snow?” Alvin asked． Clare said she 26 to walk． So they got out of the car with their son and began walking． But   27 was to come． Soon they lost their 28 and had to walk aimlessly on and on．
Night came． They were not afraid of the dark． But they were 29 that poor Alax would die of cold． However, their faith to keep Alax   30 made them filled with courage, warmth and strength． They 31 and rested in turn and then continued their walk． They had countless falls but each time true love encouraged them to rise to their   32 again．
One, two, three, …seven days passed． On the eighth day,   33 at last came from Alvin’s parents, t

he police and local people． But the young 34 had to have their feet cut off because of

the bad frost-bites(冻伤)． Fortunately, there was 35 seriously wrong with little Alax．