GK
ELEMENTS COMPOUNDS SUBSTANCES METALS AND NON METALS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Coal
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Carbon
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Sulphur
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Aluminium
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Detailed explanation-1: -Detailed Solution. Aluminium is a metal so it has a shiny appearance. Metals, in their pure state, have a shining surface. This property is called metallic lustre.
Detailed explanation-2: -The ability of a material to shine is called lustre. Gold, silver and other metals are examples of lustrous substances.
Detailed explanation-3: -Aluminum is a soft and lightweight metal. It has a dull silvery appearance, because of a thin layer of oxidation that forms quickly when it is exposed to air.
Detailed explanation-4: -Two layers of foil are pressed together and milled at the same time, because otherwise, it would break. “Where the foil is in contact with another layer, that’s the ‘dull’ side, ‘’ Reynold’s explains. “The ‘shiny’ side is the side milled without being in contact with another sheet of metal.
Detailed explanation-5: -Metals appear shiny because they contain vacant electrons. When these loose electrons come in contact with the light energy, they start vibrating and moving randomly in every direction in the metal. So, The light energy incident upon it gets reflected. Thus, metals appear shiny and lustrous.