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प्रश्न
Give a reason why elements are tabulated in a table called the ‘Periodic table’.
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उत्तर
For arranging all the elements in a systematic and simple manner. The arrangement of elements was done in the form of a table called Periodic Table in which elements are arranged in increasing order of their atomic numbers. Elements in the Periodic Table are arranged in Horizontal rows called Periods and vertical columns called groups. Metallic elements are placed on the left non-metallic on the right and noble gases on the extreme right of the Periodic table.
संबंधित प्रश्न
Write true or false
Milk is an emulsion.
Name the element used as a standard for atomic mass scale.
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(a) O
(b) S
(c) Cl
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Match the formulas of the following of acids with their correct names:
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State the variable valency of the following metal.
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write symbol with the variable valency
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Sulphide
What does the symbol '(aq.)' present in a chemical equation, mean?
The pictorial symbol for water given by the alchemists was
Define Alchemy.
