Consider an atom with 17 protons, 18 neutrons, and 17 electrons. Identify the element, determine its atomic number and mass number, and state whether it is a neutral atom or an ion.
ChemistryClass 9CBSEAnswered 12 May 2026
Answer
The element is Chlorine (Cl) because it has 17 protons (atomic number = 17). Its atomic number is 17. Its mass number is 17 (protons) + 18 (neutrons) = 35. Since the number of protons (17) equals the number of electrons (17), it is a neutral atom.
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