Question
Which has higher ionization energy: chlorine (Cl) or magnesium (Mg)? Why? Select the best answer
1. Mg; magnesium has more valence electrons than chlorine.
2.Mg; it takes more energy to pull two electrons away from magnesium(Mg) than it does to take them from chlorine(Cl).
3.Cl; it takes much more energy to pull an electron away from a valence shell that is nearly full.
4.Cl; it takes less energy to add an electron to a valence shell that is nearly full.
1. Mg; magnesium has more valence electrons than chlorine.
2.Mg; it takes more energy to pull two electrons away from magnesium(Mg) than it does to take them from chlorine(Cl).
3.Cl; it takes much more energy to pull an electron away from a valence shell that is nearly full.
4.Cl; it takes less energy to add an electron to a valence shell that is nearly full.
Answers
GPT-4o mini
The correct answer is:
**3. Cl; it takes much more energy to pull an electron away from a valence shell that is nearly full.**
### Explanation:
Chlorine (Cl) has an electron configuration of [Ne] 3s² 3p⁵, meaning it has seven valence electrons and is very close to having a full octet. Removing an electron from a nearly full outer shell requires significantly more energy because atoms generally prefer to maintain their stable electron configurations.
In contrast, magnesium (Mg) has an electron configuration of [Ne] 3s², which means it has two valence electrons. While removing these electrons does require energy, it's generally less than the energy required to remove an electron from a nearly full shell like that of chlorine. Hence, chlorine has a higher ionization energy than magnesium.
**3. Cl; it takes much more energy to pull an electron away from a valence shell that is nearly full.**
### Explanation:
Chlorine (Cl) has an electron configuration of [Ne] 3s² 3p⁵, meaning it has seven valence electrons and is very close to having a full octet. Removing an electron from a nearly full outer shell requires significantly more energy because atoms generally prefer to maintain their stable electron configurations.
In contrast, magnesium (Mg) has an electron configuration of [Ne] 3s², which means it has two valence electrons. While removing these electrons does require energy, it's generally less than the energy required to remove an electron from a nearly full shell like that of chlorine. Hence, chlorine has a higher ionization energy than magnesium.