To determine which set of atoms is ordered correctly from lowest to highest ionization energy, let us first list their ionization energies:
- Strontium (Sr): 549.5 kJ/mol
- Calcium (Ca): 589.8 kJ/mol
- Magnesium (Mg): 737.7 kJ/mol
- Beryllium (Be): 899.5 kJ/mol
Given the ionization energies, we need to identify the correct set where the elements are ordered from the lowest to the highest ionization energy.
Let’s evaluate the sets:
1. [tex]\( Sr < Ca < Mg < Be \)[/tex]
- Sr: 549.5 kJ/mol
- Ca: 589.8 kJ/mol
- Mg: 737.7 kJ/mol
- Be: 899.5 kJ/mol
This set orders the ionization energies as: 549.5, 589.8, 737.7, 899.5, which is in ascending order of ionization energy.
2. [tex]\( Sr < Mg < Ca < Be \)[/tex]
- Sr: 549.5 kJ/mol
- Mg: 737.7 kJ/mol
- Ca: 589.8 kJ/mol
- Be: 899.5 kJ/mol
This set orders the ionization energies as: 549.5, 737.7, 589.8, 899.5, which is not in ascending order as the ionization energy for Mg is greater than Ca.
3. [tex]\( Be < Mg < Ca < Sr \)[/tex]
- Be: 899.5 kJ/mol
- Mg: 737.7 kJ/mol
- Ca: 589.8 kJ/mol
- Sr: 549.5 kJ/mol
This set orders the ionization energies as: 899.5, 737.7, 589.8, 549.5, which is not in ascending order as Be has the highest ionization energy.
4. [tex]\( Be < Ca < Mg < Sr \)[/tex]
- Be: 899.5 kJ/mol
- Ca: 589.8 kJ/mol
- Mg: 737.7 kJ/mol
- Sr: 549.5 kJ/mol
This set orders the ionization energies as: 899.5, 589.8, 737.7, 549.5, which is not in ascending order as Be has the highest ionization energy.
The correct set that orders the ionization energies from the lowest to the highest is:
[tex]\[ \boxed{1} \][/tex]
Thus, the correct order of atoms from lowest to highest ionization energy is [tex]\( Sr < Ca < Mg < Be \)[/tex].
