Question

These ionization energies (Kj/mol) have been reported for element "Z":
first: 500
second: 4560
third: 6910
fourth: 9540
fifth: 13400

Which of the following elements is most likely "Z"?

1. Si
2. Mg
3. Al
4. Na
5. Cl

Is it 4. Na ?

Answer 1

yes. IT is most likely period 1, and Na is the only alkali metal there.