| 单词 | 原子量 |
| 释义 | 〔Richards〕American chemist. He won a 1914 Nobel Prize for determining the atomic weight of more than 50 elements.理查兹，狄奥多尔·威廉：(1868-1928) 美国化学家，他因为确定了五十余种元素的原子量而获得1914年诺贝尔奖〔palladium〕A soft, ductile, steel-white, tarnish-resistant, metallic element occurring naturally with platinum, especially in gold, nickel, and copper ores. Because it can absorb large amounts of hydrogen, it is used as a purification filter for hydrogen and a catalyst in hydrogenation. It is alloyed for use in electric contacts, jewelry, nonmagnetic watch parts, and surgical instruments. Atomic number 46; atomic weight 106.4; melting point 1,552°C; boiling point 3,140°C; specific gravity 12.02 (20°C); valence 2, 3, 4. See table at element 钯：一种柔软的，易拉长的，银白色的，保持光泽的金属性元素，常与铂共生，尤其在金、镍和铜矿中存在。因为它能吸收大量氢，常用作除氢的过滤器或氢化作用的催化剂。其合金可用于电子接触器、珠宝、无磁性表部件以及外科医用器具。原子序数46；原子量106.4；熔点1,552°C；沸点3,140°C；比重12.02（在20°C时）；化合价2，3，4 参见 element〔californium〕A synthetic element produced in trace quantities by helium isotope bombardment of curium. All isotopes are radioactive, chiefly by emission of alpha particles. Atomic number 98; mass numbers 244 to 254; half-lives varying from 25 minutes to 800 years. See table at element 锎：一种合成元素，由氦同位素轰击锔可得到微量的这种元素。所有同位素均是放射性元素，主要放射出α粒子。原子序数98；原子量244到254；半衰期从25分钟到800年不等 参见 element〔cadmium〕A soft, bluish-white metallic element occurring primarily in zinc, copper, and lead ores, that is easily cut with a knife and is used in low-friction, fatigue-resistant alloys, solders, dental amalgams, nickel-cadmium storage batteries, nuclear reactor shields, and in rustproof electroplating. Atomic number 48; atomic weight 112.40; melting point 320.9°C; boiling point 765°C; specific gravity 8.65; valence 2. See table at element 镉：一种质软的，蓝白色的金属元素，最初存在于锌矿、铜矿和铅矿之中，这种金属易于用刀切割，用于制造低摩擦阻力和耐疲劳的合金、焊料、牙科用的混合填料、镍镉蓄电池、核反应堆防护层和防锈电镀之中。原子序数48；原子量112.40；熔点320.9°C；沸点765°C；比重8.65；原子价2 参见 element〔uranium〕A heavy silvery-white metallic element, radioactive and toxic, easily oxidized, and having 14 known isotopes of which U 238 is the most abundant in nature. The element occurs in several minerals, including uraninite and carnotite, from which it is extracted and processed for use in research, nuclear fuels, and nuclear weapons. Atomic number 92; atomic weight 238.03; melting point 1,132°C; boiling point 3,818°C; specific gravity 18.95; valence 2, 3, 4, 5, 6. See table at element 铀：银白色的重金属元素，有放射性并且有毒，容易被氧化。已知有14个同位素，其中U238是自然界含量最多的。这种元素存在如沥青铀矿和钒钾铀矿等几种矿中，并从中提炼和加工，主要用于研究，核燃料和核武器。原子序数为92；原子量为238.03；熔点为1,132°C；沸点3,818°C；比重18.95；化合价2，3，4，5，6 参见 element〔thallium〕A soft, malleable, highly toxic metallic element, used in photocells, infrared detectors, low-melting glass, and formerly in rodent and ant poisons. Atomic number 81; atomic weight 204.37; melting point 303.5°C; boiling point 1,457°C; specific gravity 11.85; valence 1, 3. See table at element 铊：柔轻的可延展的剧毒金属元素，用于光电池、红外检测器、低熔玻璃，从前用于田鼠和蚂蚁的毒药。原子序数81；原子量204.37；熔点303.5°C；沸点1,457°C；比重11.85；化合价1或3 参见 element〔mercury〕Symbol Hg A silvery-white poisonous metallic element, liquid at room temperature and used in thermometers, barometers, vapor lamps, and batteries and in the preparation of chemical pesticides. Atomic number 80; atomic weight 200.59; melting point -38.87°C; boiling point 356.58°C; specific gravity 13.546 (at 20°C); valence 1, 2. Also called quicksilver See table at element 符号 Hg 水银，汞：一种银白色有毒金属元素，室温下呈液态，用于温度计、气压计、蒸气灯及电池中，也用于化学杀虫剂中。原子序数为80；原子量为200.59；熔点-38.87°C；沸点为356.58°C；比重为13.546（20°C时）；化合价为1,2 也作 quicksilver 参见 element〔ruthenium〕A hard white acid-resistant metallic element that is found in platinum ores and is used to harden platinum and palladium for jewelry and in alloys for nonmagnetic wear-resistant instrument pivots and electrical contacts. Atomic number 44; atomic weight 101.07; melting point 2,310°C; boiling point 3,900°C; specific gravity 12.41; valence 0, 1, 2, 3, 4, 5, 6, 7, 8. See table at element 钌：一种坚硬的白色抗酸金属元素，在铂矿中可找到它，用于加固铂和钯以制成宝石和化合成非磁性的抗磨损的工具枢纽和电接触器。原子序数44；原子量101.07；熔点2,310°C；沸点3,900°C；比重12.41；原子价0,1,2,3,4,5,6,7,8 参见 element〔lanthanum〕A soft, silvery-white, malleable, ductile, metallic rare-earth element, obtained chiefly from monazite and bastnaesite and used in glass manufacture and with other rare earths in carbon lights for movie and television studio lighting. Atomic number 57; atomic weight 138.91; melting point 920°C; boiling point 3,469°C; specific gravity 5.98 to 6.186; valence 3. See table at element 镧：一种质软、银白色、有延展性的、可塑性的稀有金属，主要是从独居石和氟碳铈矿中提取出来，用于玻璃工业及电影或电视摄影照明的碳棒灯中。原子序数57；原子量138.91；熔点920°C；沸点3,496°C；比重5.98到6.186；原子价3 参见 element〔gallium〕A rare metallic element that is liquid near room temperature, expands on solidifying, and is found as a trace element in coal, bauxite, and other minerals. It is used in semiconductor technology and as a component of various low-melting alloys. Atomic number 31; atomic weight 69.72; melting point 29.78°C; boiling point 2,403°C; specific gravity 5.907; valence 2, 3. See table at element 镐：一种在室温下是液体的稀有金属元素膨胀成固化，通常作为煤、铝土岩和其它矿中的微量元素而存在。用于半导体技术和各种低融合金的合成。原子序数31；原子量69.72；熔点27.98摄氏度；沸点2,403摄氏度；比重5.907；化合价2，3 参见 element〔cerium〕A lustrous, iron-gray, malleable metallic rare-earth element that occurs chiefly in the minerals monazite and bastnaesite, exists in four allotropic states, is a constituent of lighter flint alloys, and is used in various metallurgical and nuclear applications. Atomic number 58; atomic weight 140.12; melting point 795°C; boiling point 3,468°C; specific gravity 6.67 to 8.23; valence 3, 4. See table at element 铈：一种有光泽、铁灰色、可延展的金属稀土元素，主要存在于独居石和氟碳铈矿中，以四种同素异形体存在，是轻燧石合金的成分，在冶金和核能工业上有多种应用。原子序数58；原子量140.12；熔点795°C；沸点3,468°C；比重6.67至8.23；化合价3,4 参见 element〔aluminum〕A silvery-white, ductile metallic element, the most abundant in the earth's crust but found only in combination, chiefly in bauxite. Having good conductive and thermal properties, it is used to form many hard, light, corrosion-resistant alloys. Atomic number 13; atomic weight 26.98; melting point 660.2°C; boiling point 2,467°C; specific gravity 2.69; valence 3. See table at element 铝：一种银白色韧性金属元素，在地壳中含量最多，但只出现在混合物主要是铝土矿中。由于有良好的导电导热特性而被用来制造多种硬而轻的抗蚀合金。原子序数13；原子量26.98；熔点660.2°C；沸点2,467°C；比重2.69；化合价3 参见 element〔germanium〕A brittle, crystalline, gray-white metalloid element, widely used as a semiconductor, as an alloying agent and catalyst, and in certain optical glasses. Atomic number 32; atomic weight 72.59; melting point 937.4°C; boiling point 2,830°C; specific gravity 5.323 (at 25°C); valence 2, 4. See table at element 锗：一种银白色的脆而透明的金属元素，被广泛用作半导体，可作一种合成剂和催化剂，还被用在光学玻璃中。原子序数32；原子量72.59；熔点937.4°C；沸点2,830°C；比重5.323（在25°C时）；化合价2，4 参见 element〔bromine〕A heavy, volatile, corrosive, reddish-brown, nonmetallic liquid element, having a highly irritating vapor. It is used in producing gasoline antiknock mixtures, fumigants, dyes, and photographic chemicals. Atomic weight 79.904; atomic number 35; melting point 7.2°C; boiling point 58.78°C; valence 1, 3, 5, 7. See table at element 溴：一种比重大、易挥发、有腐蚀性的棕红色非金属液体元素，有刺鼻的气味。用于生产汽油减震剂、薰蒸剂、染料和照相用的化学品。原子量79.904；原子序数35；熔点7.2°C；沸点58.78°C；化合价1,3,5,7 参见 element〔scandium〕A silvery-white metallic element found in various rare minerals and separated as a byproduct in the processing of certain uranium ores. An artificially produced radioactive isotope is used as a tracer in studies of oil wells and pipelines. Atomic number 21; atomic weight 44.956; melting point 1,540°C; boiling point 2,850°C; specific gravity 2.99; valence 3. See table at element 钪：一种发现于许多稀有矿物中的银白色金属元素，是某种铀矿加工过程中分离出的副产品，人造放射性同位素被用作油井和油气管道的探测剂。原子序数21；原子量44.956；熔点1,540°C；沸点2,850°C；比重2.99；化合价3 参见 element〔technetium〕A silvery-gray radioactive metal, the first synthetically produced element, having 14 isotopes with masses ranging from 92 to 105 and half-lives up to 2.6×106 years. It is used as a tracer and to eliminate corrosion in steel. Atomic number 43; melting point 2,200°C; specific gravity 11.50; valence 0, 2, 4, 5, 6, 7. See table at element 锝：一种银灰色放射性金属，是第一个人工合成的元素，有十四个原子量从92到105且半衰期高达2.6×106年的同位素。用作放射追踪剂并可消除钢铁腐蚀现象。原子序数43；熔点2,200°C；比重11.50；原子价0, 2, 4, 5, 6, 7 参见 element〔titanium〕A strong, low-density, highly corrosion-resistant, lustrous white metallic element that occurs widely in igneous rocks and is used to alloy aircraft metals for low weight, strength, and high-temperature stability. Atomic number 22; atomic weight 47.90; melting point 1,660°C; boiling point 3,287°C; specific gravity 4.54; valence 2, 3, 4. See table at element 钛：一种坚固、低密度、高度抗腐蚀的带光泽的白色金属元素，广泛存在于火成岩中，由于其质量轻，牢固和抗高温的性能被用于做飞行器的合金。原子序数22；原子量47.90；熔点1,660°C；沸点3,287°C；比重4.54；原子价2,3,4 参见 element〔nitrogen〕A nonmetallic element that constitutes nearly four fifths of the air by volume, occurring as a colorless, odorless, almost inert diatomic gas, N2, in various minerals and in all proteins and used in a wide variety of important manufactures, including ammonia, nitric acid, TNT, and fertilizers. Atomic number 7; atomic weight 14.0067; melting point -209.86°C; boiling point -195.8°C; valence 3, 5. See table at element 氮：一种非金属元素，按体积计算约占空气的五分之四，是一种无色、无味几乎为惰性的双原子气体，N2，存在于各种矿物和所有的蛋白质中，广泛地运用于各种重要的生产中包括生产氨酸、硝酸、黄色炸药以及化肥。原子序数7；原子量14.0067；熔点-209.86°C；沸点-195.8°C；化合价3,5 参见 element〔calcium〕A silvery, moderately hard metallic element that constitutes approximately 3 percent of the earth's crust and is a basic component of most animals and plants. It occurs naturally in limestone, gypsum, and fluorite, and its compounds are used to make plaster, quicklime, Portland cement, and metallurgic and electronic materials. Atomic number 20; atomic weight 40.08; melting point 842 to 848°C; boiling point 1,487°C; specific gravity 1.55; valence 2. See table at element 钙：一种银色的、硬度适中的金属元素，约占地壳中各种元素的百分之三，是多数动物和植物的基本组成物之一。自然存在于石灰石、石膏、氟石以及其它化合物之中，用于制造石膏、生石灰、硅酸盐水泥以及冶金和电子材料。原子序数20；原子量40.08；熔点842到848度；沸点1,487度；比重1.55；化学价2 参见 element〔tungsten〕A hard, brittle, corrosion-resistant, gray to white metallic element extracted from wolframite, scheelite, and other minerals, having the highest melting point and lowest vapor pressure of any metal. Tungsten and its alloys are used in high-temperature structural materials; in electrical elements, notably lamp filaments; and in instruments requiring thermally compatible glass-to-metal seals. Atomic number 74; atomic weight 183.85; melting point 3,410°C; boiling point 5,900°C; specific gravity 19.3 (20°C); valence 2, 3, 4, 5, 6. Also called wolfram See table at element 钨：一种坚硬、易碎 、耐腐蚀的金属元素，颜色从灰到白，主要从黑钨矿、白钨矿和其它矿物中提取出来，它是所有金属中熔点最高，气压最低的金属。钨及钨合金可用于耐温的建筑材料；电子元件，主要是白炽灯丝；以及要求热度上兼容的玻璃至金属的密封装置的仪器。原子序数74；原子量183.85；熔点3,410°C；沸点5,900°C；比重19.3(20°C)；原子价2,3,4,5,6 也作 wolfram 参见 element〔bismuth〕A white, crystalline, brittle, highly diamagnetic metallic element used in alloys to form sharp castings for objects sensitive to high temperatures and in various low-melting alloys for fire-safety devices. Atomic number 83; atomic weight 208.980; melting point 271.3°C; boiling point 1,560°C; specific gravity 9.747; valence 3, 5. See table at element 铋：白色、晶状、易碎、高度抗磁的金属元素，用于高温敏感物体的合金中，以铸成锋利物件，多种用于防火安全设施的低熔点合金。原子序数83；原子量208.980；熔点271.3°C；沸点1560°C；比重9.747；化合价3,5 参见 element〔astatine〕A highly unstable radioactive element, the heaviest of the halogen series, that resembles iodine in solution. Its longest lived isotope has a mass number of 210 and has a half-life of 8.3 hours. Atomic number 85; melting point 302°C; boiling point 337°C; valence probably 1, 3, 5, 7. See table at element 砹：极不稳定放射性元素，在卤族元素比重最大，在溶解状态与碘相象，它最长周期的同位素原子量为210，半衰期为8.3小时。原子序数85；溶点302°C；沸点337°C；化合价可能为1、3、5、7 参见 element〔antimony〕A metallic element having four allotropic forms, the most common of which is a hard, extremely brittle, lustrous, silver-white, crystalline material. It is used in a wide variety of alloys, especially with lead in battery plates, and in the manufacture of flame-proofing compounds, paint, semiconductor devices, and ceramic products. Atomic number 51; atomic weight 121.75; melting point 630.5°C; boiling point 1,380°C; specific gravity 6.691; valence 3, 5. See table at element 锑：一种金属元素，有四个同素异形体，最常见的是一种硬而脆的银白色发光晶体物质。锑普遍用于各种合金，特别是和铅一起用于电池极板，制造防火合成物、油漆、半导体装置和陶瓷制品。原子序数为51；原子量为121.75；熔点为630.5°C；沸点1,380°C；比重为6.691；化合价为3,5 参见 element〔chlorine〕A highly irritating, greenish-yellow gaseous halogen, capable of combining with nearly all other elements, produced principally by electrolysis of sodium chloride and used widely to purify water, as a disinfectant and bleaching agent, and in the manufacture of many important compounds including chloroform and carbon tetrachloride. Atomic number 17; atomic weight 35.45; freezing point -100.98°C; boiling point -34.6°C; specific gravity 1.56 (-33.6°C); valence 1, 3, 5, 7. See table at element 氯：一种具有很大刺激性的、几乎能与所有其它元素化合黄绿色气体卤素，主要通过电解氯化纳获得，作为一种消毒及漂白剂广泛用于使水净化，以及用在包括三氯甲烷和四氯化碳在内的许多重要化合物的生产过程中。原子序数为17；原子量为35.45；冰点为零下100.98°C；沸点为零下34.6°C；比重为1.56（零下33.6°C）；化合价1，3，5，7 参见 element〔platinum〕Symbol Pt A silver-white metallic element occurring worldwide, usually mixed with other metals such as iridium, osmium, or nickel. It is ductile and malleable, does not oxidize in air, and is used as a catalyst and in electrical components, jewelry, dentistry, and electroplating. Atomic number 78; atomic weight 195.09; melting point 1,772°C; boiling point 3,827°C; specific gravity 21.45; valence 2, 3, 4. See table at element 符号 Pt 铂：一种世界范围内存在的银白色金属元素，常与其它金属，如铱、锇或镍混合，易拉长且具延展性的，在空气中不氧化，可用作催化剂，用于电学元件、珠宝，牙科学和电镀中。原子序数78；原子量195.09；熔点1,772°C；沸点3,827°C；比重21.45；化合价2,3,4 参见 element〔silicon〕A nonmetallic element occurring extensively in the earth's crust in silica and silicates, having both an amorphous and a crystalline allotrope, and used doped or in combination with other materials in glass, semiconducting devices, concrete, brick, refractories, pottery, and silicones. Atomic number 14; atomic weight 28.086; melting point 1,410°C; boiling point 2,355°C; specific gravity 2.33; valence 4. See table at element 硅：一种非金属元素，广泛存在于地壳的硅酸盐和硅石中，有非晶体和晶体的同素异形体，与其它材料掺杂或结合，用于制造玻璃、半导体材料、混凝土、砖、耐火材料、陶瓷和矽氧烷。原子序数14；原子量28.086；熔点1,410°C；沸点2,355°C；比重2.33；化合价4 参见 element〔iron〕Symbol Fe A silvery-white, lustrous, malleable, ductile, magnetic or magnetizable, metallic element occurring abundantly in combined forms, notably in hematite, limonite, magnetite, and taconite, and used alloyed in a wide range of important structural materials. Atomic number 26; atomic weight 55.847; melting point 1,535°C; boiling point 2,750°C; specific gravity 7.874 (at 20°C); valence 2, 3, 4, 6. See table at element 符号 Fe 铁：一种银白色的、有光泽、有韧性、可延展，有磁性或可被磁化的金属，以化合物形式大量存在，主要有赤铁矿、褐铁矿、磁铁矿和角岩，在许多种重要结构材料中用作合金的一种。原子序数26；原子量55.847；熔点1,535°C；沸点2,750°C；比重7.874（在20°C时）；化合物2，3，4，6 参见 element〔ytterbium〕A soft, bright, silvery rare-earth element occurring in two allotropic forms and used as an x-ray source for portable irradiation devices, in some laser materials, and in some special alloys. Atomic number 70; atomic weight 173.04; melting point 824°C; boiling point 1,196°C; specific gravity 6.972 or 6.54 (25°C) depending on allotropic form; valence 2, 3. See table at element 镱：一种柔软、明亮的银色稀土元素，存在于两种同素异形体中，被用作便携式的放射线治疗设备的X射线源，也用于一些激光物质和特殊合金中。原子序数70；原子量173.04；熔点824°C；沸点1,196°C；比重依两种同素形体6.972或6.54(25°C)；化合价2,3 参见 element〔krypton〕A whitish, inert gaseous element used chiefly in gas discharge lamps and fluorescent lamps. Atomic number 36; atomic weight 83.80; melting point -156.6°C; boiling point -152.30°C; density 3.73 grams per liter (0°C). See table at element 氪：一种微白的惰性气体元素，主要用于充气灯和荧光灯。原子序数36；原子量83.80；熔点-156.6°C；沸点-152.30°C；0°C时密度每升3.73克 参见 element〔chromium〕A lustrous, hard, steel-gray metallic element, resistant to tarnish and corrosion and found primarily in chromite. It is used as a catalyst, to harden steel alloys and produce stainless steels, in corrosion-resistant decorative platings, and as a pigment in glass. Atomic number 24; atomic weight 51.996; melting point 1,890°C; boiling point 2,482°C; specific gravity 7.18; valence 2, 3, 6. See table at element 铬：一种有光泽的、蓝灰色的坚硬金属元素。不失光泽，抗腐蚀，最早在铬铁矿中发现。用作催化剂，可加强钢合金的强度和生产不锈钢，可以做防腐镀层和玻璃制品中的颜料。原子序数24；原子量51.996；熔点1,890°C；沸点2,482°C；比重7.18；化合价2，3，6 参见 element〔rubidium〕A soft silvery-white metallic element of the alkali group that ignites spontaneously in air and reacts violently with water, used in photocells and in the manufacture of vacuum tubes. Atomic number 37; atomic weight 85.47; melting point 38.89°C; boiling point 688°C; specific gravity (solid) 1.532; valence 1, 2, 3, 4. See table at element 铷：一种银白色的软的碱性金属元素，与空气接触会立即燃烧，与水反应剧烈，用于光电池和制造真空管。原子序数37；原子量85.47；熔点38.89°C；沸点688°C；比重（固体）1.532；化合价1,2,3,4 参见 element〔lead〕Symbol Pb A soft, malleable, ductile, bluish-white, dense metallic element, extracted chiefly from galena and used in containers and pipes for corrosives, solder and type metal, bullets, radiation shielding, paints, and antiknock compounds. Atomic number 82; atomic weight 207.19; melting point 327.5°C; boiling point 1,744°C; specific gravity 11.35; valence 2, 4. See table at element 符号 Pb 铅：一种柔软、有延展性和可锻性的，蓝白色高密度金属元素，主要从方铅矿中提取，用于集装箱、耐腐蚀管道、焊料和字铅、子弹、放射性防护屏、涂料及抗爆化合物。原子序数82；原子量207.19；熔点327.5°C；沸点1,744°C；比重11.35；化合价2或4 参见 element〔magnesium〕A light, silvery-white, moderately hard metallic element that in ribbon or powder form burns with a brilliant white flame. It is used in structural alloys, pyrotechnics, flash photography, and incendiary bombs. Atomic number 12; atomic weight 24.312; melting point 649°C; boiling point 1,090°C; specific gravity 1.74 (at 20°C); valence 2. See table at element 镁：一种质轻、银白色的成条状或粉状的中性硬度金属元素，燃烧时有很亮的白色火焰。用于建筑方面的合金、焰火、闪光灯或燃烧弹。原子序号12；原子量24.312；熔点649°C；沸点1,090°C；比重1.74(20°C时）；原子价2 参见 element〔hafnium〕A brilliant, silvery, metallic element separated from ores of zirconium and used in nuclear reactor control rods, as a getter for oxygen and nitrogen, and in the manufacture of tungsten filaments. Atomic number 72; atomic weight 178.49; melting point 2,220°C; boiling point 5,400°C; specific gravity 13.3; valence 4. See table at element 铪：一种锆矿中分离出来的亮银色金属元素，用于核反应堆的控制棒，可形成氧气和氮气的保护膜，还用于钨丝的制造。原子序数72；原子量178.49；熔点2,220°C；沸点5,400°C；比重13.3；原子价4 参见 element〔boron〕A soft, brown, amorphous or crystalline nonmetallic element, extracted chiefly from kernite and borax and used in flares, propellant mixtures, nuclear reactor control elements, abrasives, and hard metallic alloys. Atomic number 5; atomic weight 10.811; melting point 2,300°C; sublimation point 2,550°C; specific gravity (crystal) 2.34; valence 3. See table at element 硼：一种柔软、棕色、无定形或结晶的非金属元素，主要从四水硼砂和硼砂中提取，用于闪光剂、推进混合物、原子反应控制剂、磨砂和硬合金中。原子序数5；原子量10.811；熔点2,300°C；沸点2,550°C；比重（晶体）2.34；化合价3 参见 element〔cesium〕A soft, silvery-white ductile metal, liquid at room temperature, the most electropositive and alkaline of the elements, used in photoelectric cells and to catalyze hydrogenation of some organic compounds. Atomic number 55; atomic weight 132.905; melting point 28.5°C; boiling point 690°C; specific gravity 1.87; valence 1. See table at element 铯：一种质地柔软的银白色韧性金属，室温时为液体，为最具正电性与碱性的元素，用作光电池和某些有机化合物氢化作用的催化剂。原子序数55；原子量132.905；熔点28.5°C；沸点°C；比重1.87；化合价1 参见 element〔zinc〕A bluish-white, lustrous metallic element that is brittle at room temperature but malleable with heating. It is used to form a wide variety of alloys including brass, bronze, various solders, and nickel silver, in galvanizing iron and other metals, for electric fuses, anodes, and meter cases, and in roofing, gutters, and various household objects. Atomic number 30; atomic weight 65.37; melting point 419.4°C; boiling point 907°C; specific gravity 7.133 (25°C); valence 2. See table at element 锌：一种蓝白色带光泽的金属元素，室温下易碎，但加热后可展延。用于制造各种合金，包括黄铜、青铜、各种焊料和镍银，以及给铁和其它金属镀锌，还用于电保险丝、阳极和仪表，以及屋面材料、檐槽和各种家庭用具。原子序数30；原子量65.37；熔点419.4°C；沸点907°C；比重7.133（在25°C时）；化合价2 参见 element〔beryllium〕A high-melting, lightweight, corrosion-resistant, rigid, steel-gray metallic element used as an aerospace structural material, as a moderator and reflector in nuclear reactors, and in a copper alloy used for springs, electrical contacts, and nonsparking tools. Atomic number 4; atomic weight 9.0122; melting point 1,278°C; boiling point 2,970°C; specific gravity 1.848; valence 2. See table at element 铍：一种高熔点、质轻、抗腐蚀、坚硬的青灰色金属元素，用作宇宙空间结构材料，如核反应器中的减速剂和反射体，铍铜合金用于制造弹簧、电接触器和无电花工具。原子序数4；原子量9.0122；熔点1,278°C；沸点2,970°C；比重1.848；化合价2 参见 element〔niobium〕A silvery, soft, ductile metallic element that occurs chiefly in columbite-tantalite and is used in steel alloys, arc welding, and superconductivity research. Atomic number 41; atomic weight 92.906; melting point 2,468°C; boiling point 4,927°C; specific gravity 8.57; valence 2, 3, 5. See table at element 铌：一种象银的、柔软的、可延展的金属元素，主要存在于铌钽物中，用于钢铁合金、弧形焊接以及超导（电）性研究中。原子序数41；原子量92,906；熔点2,468°C；沸点4,927°C；比重8.57；化合价2,3,5 参见 element〔arsenic〕Symbol As A highly poisonous metallic element having three allotropic forms, yellow, black, and gray, of which the brittle, crystalline gray is the most common. Arsenic and its compounds are used in insecticides, weed killers, solid-state doping agents, and various alloys. Atomic number 33; atomic weight 74.922; valence 3, 5. Gray arsenic melts at 817°C (at 28 atm pressure), sublimes at 613°C, and has a specific gravity of 5.73. See table at element 符号 As 砷：一种有剧毒的金属元素，有黄、黑、灰三种同素异形体，其中质脆，结晶体的灰色形体最为常见。砷及其化合物用于杀虫剂，除草剂，固体添加剂和各种合金。原子序数33；原子量74.922；化合价3，5。灰色砷熔点为817°C（在28气压时），613°C升华，比重5.73 参见 element |
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