首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
共用题干 Where Has the Salt Come from?Every now and then,we meet a fact about ou...
共用题干 Where Has the Salt Come from?Every now and then,we meet a fact about ou...
admin
2020-12-24
35
问题
共用题干
Where Has the Salt Come from?
Every now and then,we meet a fact about our earth that makes us feel strange and no
answer for the fact has yet been found.Such a fact is the existence of salt in the oceans.
How did it get there?
We simply do not know how the salt got into the ocean!We do know,of course,that
salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's
surface is constantly being dissolved(溶解)and is passing into the ocean.
But we do not know whether this can explain the huge quantity of salt in oceans.If all
the oceans were dried up,enough salt would be left to build a wall 180 miles high and a
mile thick. Such a wall would reach once around the world at the Equator(赤道)!
The common salt that we all use is produced from seawater or the water of salt lakes,
from salt springs(源泉)and from deposits of rock salt. The concentration(浓度)of salt in
seawater ranges from about three percent to three-and-one-half percent. The Dead Sea,
which covers an area of about 340 square miles,contains about 11,600,000,000 tons of
salt!
On the average, a gallon(加仑)of seawater contains about a quarter of a pound of
salt.The beds of rock salt that are found in various parts of the world were all originally
formed by the evaporation(蒸发)of seawater millions of years ago. It is believed that the
thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had
been evaporated.
Most commercial salt is obtained from rock salt.The usual method is to drill wells(井)
down to the salt beds. Pure water is pumped down(抽进去)through a pipe. The water
dissolves the salt and it is forced through another pipe up to the surface.
选项
Beds of rock salt are found in every part of the world.
A:Right
B:Wrong
C:Not mentioned
答案
A
解析
转载请注明原文地址:https://ti.zuoweng.com/ti/6klQKKKQ
相关试题推荐
共用题干 RiseinNumberofCancerSurvivorsCanceristhesecondleadingcauseof...
共用题干 RiseinNumberofCancerSurvivorsCanceristhesecondleadingcauseof...
共用题干 FemaleBullfightingItwasaunique,eye-catchingsight:anattractivewom...
共用题干 FemaleBullfightingItwasaunique,eye-catchingsight:anattractivewom...
共用题干 FemaleBullfightingItwasaunique,eye-catchingsight:anattractivewom...
共用题干 第三篇GlobalCancerRatestoRiseby50%by2020Thenumberofnewcancerc...
共用题干 第三篇GlobalCancerRatestoRiseby50%by2020Thenumberofnewcancerc...
共用题干 SleepLetsBrainFileMemoriesTosleep.Perchancetofile?Findingspubli...
共用题干 第三篇ScientificAttitudeWeallknowthatscienceplaysanimportantrole...
共用题干 第三篇ScientificAttitudeWeallknowthatscienceplaysanimportantrole...
随机试题
下列关于签订二手房买卖合同应注意的事项的表述中,正确的有( )。 A、房地产
在项目管理规划大纲中,收尾管理规划包括的内容有()
下列说法正确的是()。 Ⅰ.封闭式基金有固定存续期 Ⅱ.封闭式基金的基金份
商业银行人民币存款包括个人存款、单位存款和()。
—定量理想气体,从同一状态开始,分别经历等压、等体和等温过程。若气体在各过程中吸
不参与DNA切除修复的酶是( ) A.核酸外切酶 B.核酸内切酶 C.D
昼夜分阴阳,属于“阳中之阴”是A:前半夜B:下午C:上午D:中午E:后半夜
患者,男,36岁,左面部肿胀3年,无任何不适。近期引起面部畸形,牙齿移位咬合错乱。X线片示左上颌骨局限性膨胀、骨密度降低,其中可见不规则钙化。最可能的诊断是A.
某钢筋混凝土基础工程,包括支模板、绑扎钢筋、浇筑混凝土三道工序,每道工序安排一个专业施工队进行,分三段施工,各工序在一个施工段上的作业时间分别3天、2天、...
漏电保护又称为剩余电流保护。漏电保护是一种防止电击导致严重后果的重要技术手段。但是,漏电保护不是万能的。下列触电状态中,漏电保护不能起保护作用的是( )。A.