An ion with mass number 56 contains 3 units of positive charge and 30.4% more neutrons than electrons. Assign the symbol to this ion.
Let the number of electrons present in ion ,S3+ = x
∴ Number of neutrons in it = x + 30.4% of x = 1.304 x
Since the ion is tripositive,
⇒ Number of electrons in neutral atom = x + 3
∴ Number of protons in neutral atom = x + 3
Now mass number = no of protons + no of neutrons
56 = x + 3 + 1.304x
Or 2.304x = 53
Or x = 23
Therefore no of protons = atomic no = x + 3 = 23 + 3 = 26
∴ The symbol of the ion
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An atom contains 5.6% more neutrons than protons.The atomic mass is 56.Than atomic number is?