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Diagonal Relationship between Beryllium and Aluminium || Relation between Beryllium and Aluminium

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  Diagonal Relationship between Beryllium and Aluminium The ionic radius of Beryllium (Be 2+) is estimated to be nearly 31 pm; the charge/radius ratio Or e/m ratio is nearly the same as that of the Al 3+ ion. Hence beryllium resembles aluminium in these ways. Some of the similarities are given below: » Like Aluminium, Beryllium(be) is not readily attacked by acids H+ donor because of the formation of an oxide film on the surface of the metal by reacting with oxygen, i.e. they are rendered passive by nitric acid. » Beryllium hydroxide[[Be(OH)4]2] dissolves in excess of alkali to give a beryllate ion, [ Be(OH)4]2– just as aluminium hydroxide[Al(OH)3] gives aluminate ion, [Al(OH)4] » The chlorides of metals beryllium and aluminium have Cl– bridged chloride structure in vapour phase. Both the chlorides are soluble in organic solvents and are strong as Lewis acids They are used as Friedel Craft catalysts. » Beryllium(Be) and aluminium(Al) ions have strong tendency to form complexes, (Be...
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PHYSICAL WORLD

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THE p-BLOCK ELEMENTS

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Computer science MCQ questions Class 12 Python

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Distinction between Electromagnetic Waves and Matter Waves

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  Difference   between Electromagnetic Waves and Matter Waves » Electromagnetic waves 1. Electromagnetic waves are associated with electric and magnetic fields perpendicular to each other and to the direction of propagation of radiation. 2. Electromagnetic waves can be radiated into space or emitted. 3. They do not require any medium for propagation i.e., these waves can pass through vacuum. 4. All electromagnetic waves travel with the same velocity.  5. The velocity of all electromagnetic waves is equal to that of light (3 x 108 m/s). 6. The wavelengths of electromagnetic radiation are much large .   » Matter waves 1. Matter waves may not be associated with electric and magnetic fields. 2. Matter waves are neither radiated into space nor emitted by the particles. These are simply associated with the particles 3. They require medium for propagation i.e., these waves cannot pass through vacuum. 4. Matter waves travel with different vel...
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