首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Chlorine is a mainstay in most swimming pools in the United States, and is used to eradicate bacteria. A bacteria-free pool will
Chlorine is a mainstay in most swimming pools in the United States, and is used to eradicate bacteria. A bacteria-free pool will
admin
2017-06-30
62
问题
Chlorine is a mainstay in most swimming pools in the United States, and is used to eradicate bacteria. A bacteria-free pool will usually ensure that swimmers won’t contract a serious illness if they spend time in, and possibly ingest the water. When chlorine is added to pool water, a chemical reaction occurs whereby the chlorine breaks down into a legion of chemicals that combine to kill bacteria that may be in water. These chemicals, specifically hypochlorous acid and hypochlorite ion, eliminate bacteria by annihilating and then oxidizing the abhorrent cells. When this chemical reaction occurs, the bacteria are rendered essentially harmless. This chemical reaction doesn’t occur immediately — individual components within chlorine take varying amounts of time to interact with the bacteria, creating an almost time-release-type of kill in the pool water.
Chlorine must be regularly replenished. As they react, the hypochlorous acid and hypochlorite ion combine to create a particular acceptable pH level in the pool water. A pH is a measure of the alkalinity and acidity present; a pH value of 7 represents a neutral value, and 7. 4 is the pH value of the human tear. The pH ratio must be regularly monitored to ensure a consistent optimum ram — one usually kept within the spectrum of 7 to 8 as measured by a reliable pH measuring kit. As the chemicals in chlorine complete their reactions, they break down and are no longer effective in keeping the pool water neutralized. Additional chlorine must be added to water at specific times. Outdoor pools that are in direct sunlight need to have water added more often because the chemical reaction time for chlorine is increased and its effectiveness water added more often because the chemical reaction time for chlorine is increased and its effectiveness is reduced in these conditions. Since the hypochlorite ion is an especially potent chemical capable of fading fabrics and paint, most people are meticulous about rinsing chlorine from potentially affected areas. Although chlorine is inexpensive and widely available, some people find the bleach smell to be repugnant and the, distinct aroma present at many swimming pools to be overwhelming. These people may not be able to enjoy aquatic pursuits in those pools that employ chlorine as a cleansing agent. Other people may find that inhaling chlorine at the high levels present around some pools may be difficult to tolerate. Still others may experience skin irritation after swimming in a pool containing chlorine. Although there are other chemicals and compounds available to clean swimming pools, they may be prohibitively expensive or incapable of killing all types of bacteria present in the water.
Based on the passage, which statement is probably NOT true of chlorine?
选项
A、It can be harmful if swallowed.
B、Occasional high levels in pool water are probably not harmful.
C、It can kill most common types of pool water bacteria.
D、A pool’s size will dictate the amount needed.
答案
A
解析
排除题。文章说人们在游泳的时候很有可能呛水,因而可能会感染严重的疾病,氯气的消毒作用使人们不必担心这个问题,它对人体是无害的,所以选项A的表述错误,答案选A。
转载请注明原文地址:https://kaotiyun.com/show/OcFO777K
0
考博英语
相关试题推荐
Thegreatchariotofsociety,whichforsolonghadrundownthegentleslopeoftradition,nowfounditselfpoweredbyaninterna
Ahundredyearsagoitwasassumedandscientifically"proved"byeconomiststhatthelawsofsocietymakeitnecessarytohave
Ahundredyearsagoitwasassumedandscientifically"proved"byeconomiststhatthelawsofsocietymakeitnecessarytohave
Ifthebatik’sstatementagreeswithmybankbalance,itdoesnotfollowindisputablythatthebalanceiscorrect.
Insuchachanging,complexsocietyformerlysimplesolutionstoinformationalneedsbecomecomplicated.Manyoflife’sproblems
Althoughitisonlyasmallbusiness,its_____issurprisinglyhigh.
LetushopethatthewishexpressedbytheUnitedKingdomrepresentativetoseehisstatementfollowedbysimilardeclarationsb
Themulti-billion-dollarWesternpopmusicindustryisunderfire.ItisbeingblamedbytheUnitedNationsforthedramaticris
Everyoneitseemshasahealthproblem.AfterpouringbillionsintotheNationalHealthService,Britishpeoplemoanaboutdirty
随机试题
A.对乙酰氨基酚B.甲巯咪唑C.胰岛素D.甲状腺素E.氯硝西泮乙型肝炎患者皮下注射干扰素,1个月后出现嗜睡、体重增加,体检查出甲状腺功能减退。药师建议可口服
政治学研究常用的方法有哪些?
放射性疾病其类型有
侵蚀性葡萄胎和绒毛膜癌均可发生于
境内自然人申请开立证券账户,需提供的材料有( )。
将投资分为对内投资和对外投资的标志是()。
其他应收款的范围包括()。
人在晚上听钟表的滴答声,会感觉滴答声一时强一时弱。这体现了注意的()。
双面心理指人们在工作、学习等方面表现出来的一方面十分投入,加倍努力,另一方面又心生厌恶甚至排斥的矛盾心理现象。下列不属于双面心理的是()。
Youmaysaythatthebusinessofmarkingbooksisgoingtoslowdownyourreading.【C1】______probablywill.That’soneofthe【C2】
最新回复
(
0
)