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An element X has a mass number 4 and ato...

An element X has a mass number 4 and atomic number 2. Write the valency of this element.

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The element X with mass number 4 and atomic number 2 is helium (He) .Ity has 2 electrons (maximum possible) in its only shell which is k shell .Therefore , the valency of the element is zero.
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DINESH PUBLICATION-STRUCTURE OF ATOM -Short Answer Question
  1. complete the following table:

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  2. An element is represented as overset(16)underset(8)X.Find: (a) The n...

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  3. The electronic configuration of potassium (K) is 2,8,8,1 instedad of 2...

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  4. Show the electron distribution in magnesium atom and magnesium ion dia...

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  5. The composition of two atoms A and B is given: (a) What are the m...

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  6. (a) what is the relationship between two elements x and y whose atomic...

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  7. write the elctron distrubution of oxygen atom .How many valence elect...

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  8. (a) Why does helium have zero valecy? (b) Name the secientist and h...

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  9. Which observations in scatteing experiment led Rutherford to make the ...

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  10. Write the two postulates of Thomson's model o fan atom .What were the ...

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  11. (a) how many neutrons are present in c-14 isotope of carbon? (b) ho...

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  12. What information do you get from the figure about the atomic number, m...

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  13. In response to a question, a student stated that in an atom, the numbe...

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  14. Calculate the number of neutrons present in the nucleus of an element ...

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  15. Match the names of the Scientists given in Column A with their contrib...

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  16. The atomic number of calcium and argon are 20 and 18 respectively, but...

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  17. Complete the table on the basis of information available in the symbol...

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  18. Helium atom has 2 electrons in its valence shell but its valency is no...

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  19. Fill in the blanks in the following statements: (a) Rutherford's al...

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  20. An element X has a mass number 4 and atomic number 2. Write the valenc...

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