Consider the first () and second () ionization enthalpies of sodium () and magnesium (). Which of th — s Block Elements Chemistry Question

💡 Solution & Explanation

Mg has a higher $IE_1$ than Na due to its smaller size and fully filled 3s orbital ($3s^2$). However, Na has a massively higher $IE_2$ because removing a second electron requires breaking into a highly stable, tightly bound noble gas core ($2p^6$), whereas Mg simply loses its second valence electron.