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Structure of the Atom — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceStructure of the Atom3 Marks
Question
An element X has a mass number = 37 and it contains 17 protons.
  1. Write the symbolic representation of the element.
  2. Find the number of neutrons and electrons in the element.
  3. Write the electronic configuration of the element.
✓

Answer

The mass number of the element X = 37

Number of protons = 17

  1. Symbolic representation is:

Element = Aluminium (Al)

  1. Number of neutrons = 37 - 17 = 20

Number of the electrons are = 17

  1. Electronic configuration is 2, 8, 7

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