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Platinum
One of the platinum elements in Group 8 on the periodic table.
Titanium
A metallic element in Group 4A on the periodic table.
Iridium
One of the platinum elements in Group 8 on the periodic table.
Symbol
Pt
Ti
Ir
Atomic Number
78
22
77
Atomic weight
195.08
47.88
192.22
Oxidation States
+2, +4
+2, +3, +4
+3, +4
Electronegativity
2.2
1.6
2.2
State at RT
Solid
Solid
Solid, Metal
Melting Point
2045
1933
2683
Boiling Point
4100
3560
4403
Properties

A silvery-white valuable metal, platinum is harder than silver, but also flexible and malleable. While platinum is definitely susceptible to cold working, most of the times it is processed at temperatures ranging from 800 to 1,000 degrees Celsius. When a small amount of iridium is added, platinum noticeably gains in hardness, but loses some of its malleability. Because it expands at almost the same rate as glass, it is also used to connect various glass tools. It stays in a very stable state within the air or water, not changing its state even when heated. It is also durable against acidic and alkaline effects. However, it melts slowly in aqua regia and corrodes when heated along with caustic alkali. It also reacts in heat to such other elements as fluoride, chloride, sulfur, and selenium. It absorbs carbon at a high temperature and discharges it back when cooled. This is when the surface of platinum becomes malleable. Therefore, it is advised that you avoid heating platinum up with coals, corks, or carbon-rich reducible flames. It can be mixed with arsenic, antimony, bismuth, tin, lead, and so forth to create alloys whose melting points are much lower than that of pure platinum. Platinum, in the form of fine powder, can absorb an amount of hydrogen that is over 100 times as large as its own volume. Heat-applied platinum lets hydrogen permeate itself. Platinum also absorbs oxygen and helium: absorbed hydrogen and oxygen is then activated. This makes platinum an important catalyst in the process of oxidation and reduction.

A silvery-white metal, pure titanium is malleable and flexible, but gains in hardness upon heating. Given its resistance to corrosion, titanium is one of the most important elements in various industries. It can be found in two different crystalline types: alpha () and beta (). The hexagonal alpha type maintains a stable state in room temperature. When heated beyond 882 degrees Celsius, it turns into the cubic beta system. With the hardness of 4.0, it is extremely vulnerable in cold and can be even turned into powder. When heated, it can be elongated in linear shapes. It is almost as strong as carbon steel, twice as strong as steel and six times as strong as aluminium. It has little heat-conductivity or heat-expandability and changes little in terms of strength under 400 degrees Celsius. While stable in the air, it turns into titania when heated up in oxygen. Titanium also reacts to hallogens in heat. It is less corrosive than steel in acid. It is only second to platinum in terms of corrosion-resistance in seawater. Titanium is also used along with various other materials to create alloys.

A silvery-white metal, this unmealleable, brittle material is limited in terms of processability and cannot be processed at all when it contains even a minuscule amount of other substances. Strong against acidic or alkaline effects and even the aqua regia, iridum still melts in strong chloric acid when heated in the presence of sodium perchlorate. When heated in the air, iridium begins to oxidize at 800 degrees Celsius or higher. Because its oxidants dissolve at high temperatures, it no longer oxidizes at 1140 degrees Celsius or beyond. It reacts to sulfur and phosphorus in heat, and even more easily, relatively speaking, to chloride. Iridium compounds are found in the valences of 1, 2, 3, 4, and 6, 3 being the most common.