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प्रश्न
What is variable valency? Name two elements having variable valency and state their valencies.
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उत्तर
Variable valency: Some elements exhibit more than one valency. They are said to have variable valency, e.g. Iron, copper, tin, lead.
Iron Fe Fe2+ or Fe3+
Copper cu cu+ or cu2+
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संबंधित प्रश्न
What are the atomic numbers of elements whose outermost electrons is represented by 3p5?
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Fill in the following blanks :
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| 10 | 22 | _________ | _________ | _________ | _________ |
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The amount of substance which contains the same number of units as the number of atoms in carbon-12.
