JEE AdvancedChemistryPeriodic Table and PeriodicityNumerical+3 / −1
The 1st, 2nd and 3rd ionisation enthalpies, I1, I2 and I3, of four atoms with atomic numbers n, n + 1, n + 2, and n + 3, where n < 10, are tabulated below. What is the value of n? 

Numerical answer