GK
CHEMISTRY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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high density
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high polishing
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chemical inertness
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presence of free electrons
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Detailed explanation-1: -The lustre of a metal is due to the reflection of light which is attributed to the presence of free moving electrons in the metal. Since the electrons are free, they oscillate at a collective frequency which prevents any incoming light from entering or passing through the metal.
Detailed explanation-2: -Lustre of metal is attributed to loosely bound electrons present in the valence shell of metal atoms.
Detailed explanation-3: -Electrons absorb incident light energy and are excited from lower to higher, empty energy levels. The excited electrons will then return to lower energy levels and emit the energy difference as a photon. So, they are the reason for Gold Mineral lustre properties.
Detailed explanation-4: -Metals are lustrous (or shiny), and can be polished:-Any shining surface is called as lustrous. For example, gold, silver and copper are shiny metals and they can be polished. The property of a metal of having a shining surface is called ‘metallic lustre’.