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प्रश्न
Write two reasons responsible for late discovery of noble gases ?
उत्तर
Two reasons for late discoveries of noble gases are:-
(a) They are very inert.
(b) They are present in extremely low concentrations in our environment.
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संबंधित प्रश्न
What is meant by 'group' in the modern periodic table? How do the following change on moving from top to bottom in a group?
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(iv) Metallic character of element
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(c) Is 'M' a metal or a non-metal.
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An oxide which dissolves in water forming an acid.
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