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Name: holmium
Symbol: Ho
Atomic number: 67
Atomic weight: 164.93032 (2)
Group in periodic table:
Group name: Lanthanoid
Period in periodic table: 6 (lanthanoid)
Block in periodic table: f-block
CAS registry ID: 7440-60-0
Holmium is relatively soft and malleable, and is stable in dry air at room temperature. It oxidises rapidly in moist air and at elevated temperatures. The metal has unusual magnetic properties. The metal is a rare earth metal found in monazite, gadolinite and other minerals.
Name: cerium
Symbol: Ce
Atomic number: 58
Atomic weight: 140.116 (1) g
Group in periodic table:
Group name: Lanthanoid
Period in periodic table: 6 (lanthanoid)
Block in periodic table: f-block
CAS registry ID: 7440-45-1
Metallic cerium is prepared by reduction techniques, such as by reducing cerous fluoride with calcium, or by electrolysis of molten cerous chloride or other cerous halides.
Cerium is an iron-grey lustrous metal. It is malleable, and oxidises very readily at room temperature, especially in moist air. Except for europium, cerium is the most reactive of the rare-earth metals. It slowly decomposes in cold water, and rapidly in hot water. Alkali solutions and dilute and concentrated acids attack the metal rapidly. The pure metal may ignite when scratched with a knife.
It is the most abundant of the rare earth metals and is found in minerals including allanite, monazite, cerite, and bastanite. There are large deposits found in India, Brazil and the USA.
Name: lanthanum
Symbol: La
Atomic number: 57
Atomic weight: 138.9055 (2) g
Group in periodic table:
Group name:
Period in periodic table: 6 (lanthanoid)
Block in periodic table: f-block
CAS registry ID: 7439-91-0
Lanthanum is silvery white, malleable, ductile, and soft enough to be cut with a knife. It is one of the most reactive of the rare-earth metals. It oxidises rapidly when exposed to air. Cold water attacks lanthanum slowly, and hot water attacks it much more rapidly. The metal reacts directly with elemental carbon, nitrogen, boron, selenium, silicon, phosphorus, sulphur, and with halogens. It is a component of, misch metal (used for making lighter flints).
123456
Name: neodymium
Symbol: Nd
Atomic number: 60
Atomic weight: 144.24 (3) g
Group in periodic table:
Group name: Lanthanoid
Period in periodic table: 6 (lanthanoid)
Block in periodic table: f-block
CAS registry ID: 7440-00-8
Neodymium is present in misch metal to the extent of about 18%. The metal has a bright silvery metallic lustre. Neodymium is one of the more reactive rare-earth metals and quickly tarnishes in air, forming an oxide that spalls off and exposes the metal to further oxidation. It is one of the rare earth metals.
Name: praseodymium
Symbol: Pr
Atomic number: 59
Atomic weight: 140.90765 (2)
Group in periodic table:
Group name: Lanthanoid
Period in periodic table: 6 (lanthanoid)
Block in periodic table: f-block
CAS registry ID: 7440-10-0
Praseodymium is soft, silvery, malleable, and ductile. It was prepared in relatively pure form in 1931. It is somewhat more resistant to corrosion in air than europium, lanthanum, cerium, or neodymium, but it does develop a green oxide coating that "spalls" away when exposed to air. The metal should be stored under an inert atmosphere or under mineral oil or petroleum.
The rare-earth oxides, including Pr2O3, are among the most refractory substances known. It is a component of misch metal, used for lighter flints, and of the glass in welders' goggles.
Name: antimony
Symbol: Sb
Atomic number: 51
Atomic weight: 121.760 (1) g
Group in periodic table: 15
Group name: Pnictogen
Period in periodic table: 5
Block in periodic table: p-block
CAS registry ID: 7440-36-0
Metallic antimony is an extremely brittle metal of a flaky, crystalline texture. It is bluish white and has a metallic lustre. It is not acted on by air at room temperature, but burns brilliantly when heated with the formation of white fumes. It is a poor conductor of heat and electricity.
Antimony and its compounds are toxic. It is found mostly with other minerals and in stibnite.
123456
Name: silver
Symbol: Ag
Atomic number: 47
Atomic weight: 107.8682 (2) g
Group in periodic table: 11
Group name: Coinage metal
Period in periodic table: 5
Block in periodic table: d-block
CAS registry ID: 7440-22-4
Silver is somewhat rare and expensive, although not as expensive as gold. Slag dumps in Asia Minor and on islands in the Aegean Sea indicate that man learned to separate silver from lead as early as 3000 B.C. Pure silver has a brilliant white metallic lustre. It is a little harder than gold and is very ductile and malleable. Pure silver has the highest electrical and thermal conductivity of all metals, and possesses the lowest contact resistance. Silver iodide, AgI, is (or was?) used for causing clouds to produce rain.
Silver is stable in pure air and water, but tarnishes when exposed to ozone, hydrogen sulphide, or air containing sulphur. It occurs in ores including argentite, lead, lead-zinc, copper and gold found in Mexico, Peru, and the USA.
Name: tin
Symbol: Sn
Atomic number: 50
Atomic weight: 118.710 (7) g
Group in periodic table: 14
Group name:
Period in periodic table: 5
Block in periodic table: p-block
CAS registry ID: 7440-31-5
Ordinary tin is a silvery-white metal, is malleable, somewhat ductile, and has a highly crystalline structure. Due to the breaking of these crystals, a "tin cry" is heard when a bar is bent. The element has two allotropic forms. On warming, grey, or a-tin, with a cubic structure, changes at 13.2°C into white, or b-tin, the ordinary form of the metal. White tin has a tetragonal structure. When tin is cooled below 13.2°C, it changes slowly from white to grey. This change is affected by impurities such as aluminium and zinc, and can be prevented by small additions of antimony or bismuth. The conversion was first noted as growths on organ pipes in European cathedrals, where it was thought to be the devils work. This conversion was also speculated to be caused microorganisms and was called "tin plague" or "tin disease".
Tin resists distilled, sea, and soft tap water, but is attacked by strong acids, alkalis, and acid salts. Oxygen in solution accelerates the attack. When heated in air, tin forms SnO2. It is, or was, used to plate steel, making "tin cans". Tin is used as one component in bell metals.
Name: xenon
Symbol: Xe
Atomic number: 54
Atomic weight: 131.29 (2)
Group in periodic table: 18
Group name: Noble gas
Period in periodic table: 5
Block in periodic table: p-block
CAS registry ID: 7440-63-3
Xenon is a "noble" or "inert" gas present in the atmosphere to a small extent. Xenon is present in the Martian atmosphere to the extent of about 0.08 ppm. Before 1962, it was generally assumed that xenon and other noble gases were unable to form compounds. Among the compounds of xenon now reported are xenon hydrate, sodium perxenate, xenon deuterate, difluoride, tetrafluoride, hexafluoride, and XePtF6 and XeRhF6. The highly explosive xenon trioxide, XeO3, is known.
Metallic xenon is produced by applying several hundred kilobars of pressure. Xenon in a vacuum tube produces a blue glow when excited by an electrical discharge and finds use in strobe lamps. It is an odourless, colourless, inert gas.
Name: cadmium
Symbol: Cd
Atomic number: 48
Atomic weight: 112.411 (8) g
Group in periodic table: 12
Group name:
Period in periodic table: 5
Block in periodic table: d-block
CAS registry ID: 7440-43-9
Cadmium is a soft, bluish-white metal and is easily cut with a knife. It is similar in many respects to zinc. Interestingly, aa characteristic cadmium "scream" is heard on bending a cadmium bar (such as that illustrated above). Cadmium and its compounds are highly toxic. Silver solder, which contains cadmium, should be handled with care.