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
Learn about Noble Gases (惰性气体) 1 Have you ever ridden on a balloon? spots o行...
Learn about Noble Gases (惰性气体) 1 Have you ever ridden on a balloon? spots o行...
admin
2020-12-24
43
问题
Learn about Noble Gases (惰性气体)
1 Have you ever ridden on a balloon? spots o行er balloon rides in order for people to see the beauty of a place A balbon contains a noble gas called helium (氦).Formerly,balloons contains hydrpgen but hydrogen is very flammable and dangerous when uncontrolled.Therefore eople lifted to helium,which is safer. Helium is safe because it has the properties of the noble gases.
2 People once believed that noble gases couldn’t Chemically react at all. For this reason,they were called inert gases (惰性气).They we are also listed under Group 0 in the old periodic table because scientists believed that the gases have zero valence (价)electrons in their outer shell .This was later prove to be untrue when some noble gas compounds were discovered.
3 The gases are elements,which share similar properties.These properties include being monoatomic,colorless,odorless,being ablel conduct electricity,and having low chemical reactivity. Noble gases include HeMurJ,Neon,Argon,Krypton, Xenon and Radon. These are all found in Group 18,in the rightmost column of the periodic table. If you look at the periodic table,you will elements are the only ones,whichdo not have a charge. Helium has the molecular (分子的)weight while Radon is the heaviest.
4 Remember that chemical reactions occur because atoms have valence electrons,which are electrons in their outer she". When the outer shell is “unfied” or the electrons is not yet complete,the atom is more reactive. Noble gases have a full outer
shell,meaning that they have complete electrons in their outer shell varies. For instance, the outer shell of Helium has 2 valence electrons while the outer shell of Xenon has 8 electrons. Nowadays,there remains to be a few noble gases because of the
low chemical reactivity of these said gases.
5 Because of their properties,noble gases have many important applications. They are widely used in medicine and industries. For instance,liquid Helium is used for superconducting magnets (磁体). These magnets are very important in physics and medicine. When a doctor suspects that a person’s brain has been damaged,he might request for Magnetic Resonance Imaging (MRI) .MRI allows the doctor to “see” the brain, without operating on the patient.
选项
A lightest
B reactive
C important
D complete
E flammable
F unnecessary
Nobie gases are not very chemically __________.
答案
B
解析
第二段第一句中的react可以甩be reactive替换。
转载请注明原文地址:https://ti.zuoweng.com/ti/qzsQKKKQ
相关试题推荐
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manytou...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manytou...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manytou...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manyto...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manyto...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?spotso行...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?spotso行...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?spotso行...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?spotso行...
LearnaboutNobleGases(惰性气体) 1Haveyoueverriddenonaballoon?Manytou...
随机试题
以下疾病属于常染色体显性遗传病的是 A.毛囊角化病 B.银屑病 C.湿疹
招标人或招标代理机构在媒介发布招标公告时,应当注意()。
党对公安工作领导的全面性,就是要求公安机关全面地接受党在( )上的领导。
个人教育贷款的借款人为受教育人的,毕业后一时难以找到工作,其父母等关系人又因失业
下列适合购买利率下限期权的有()。
会计电算化对会计报表的处理,应满足以下()报表的编制要求。
民用建筑防火检查应重点注意查看一些特殊的场所,下列关于幼儿园、儿童活动场所和老年人活动场所平面布置的说法中,正确的有()。A.某独立建造的老年公寓耐火等级为二
和解少阳的代表方剂是A.四逆散B.逍遥散C.大柴胡汤D.葛根芩连汤E.小柴胡汤
因经纪服务合同的权利义务不等而产生纠纷是源于房地产经纪人的不良心态,是()缺失的表现。A:道德B:诚信C:法律知识D:专业知识
民用爆破器材是用于非军事目的的各种炸药及其制品和火工品的总称,主要包括工业炸药、起爆器材、专用民爆器材,下列器材中,属于专用民爆器材的是()A:电雷管B:火雷