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The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
A chemical bond is the association of atoms or ions to form molecules, crystals, and other structures. The bond may result from the electrostatic force between oppositely charged ions as in ionic bonds or through the sharing of electrons as in covalent bonds , or some combination of these effects.
The following table provides the reduction potentials of the indicated reducing agent at 25 °C. For example, among sodium (Na), chromium (Cr), cuprous (Cu +) and chloride (Cl −), it is Na that is the strongest reducing agent while Cl − is the weakest; said differently, Na + is the weakest oxidizing agent in this list while Cl is the strongest.
The term noble metal (also for elements) is commonly used in opposition to base metal. Noble metals are less reactive, resistant to corrosion or oxidation, [49] unlike most base metals. They tend to be precious metals, often due to perceived rarity. Examples include gold, platinum, silver, rhodium, iridium, and palladium.
The physical and chemical properties of the alkali metals can be readily explained by their having an ns 1 valence electron configuration, which results in weak metallic bonding. Hence, all the alkali metals are soft and have low densities, [5] melting [5] and boiling points, [5] as well as heats of sublimation, vaporisation, and dissociation.
Cubic boron nitride is insoluble in iron, nickel, and related alloys at high temperatures, but it binds well with metals due to formation of interlayers of metal borides and nitrides. It is also insoluble in most acids, but is soluble in alkaline molten salts and nitrides, such as LiOH, KOH, NaOH/Na 2 CO 3, NaNO 3 which are used to etch c-BN. [32]