Multiple Choice
Which element forms an ion with an electron configuration of [Ar] and a 2− charge?
3
views
2. Atoms & Elements
Ions
Struggling with General Chemistry?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Which of the following atoms or ions is NOT isoelectronic with the others?
A
Mg^{2+}
B
Na^+
C
F^-
D
Ne
Verified step by step guidance1
Understand the concept of isoelectronic species: atoms or ions that have the same number of electrons are called isoelectronic.
Determine the number of electrons in each species by subtracting the charge from the atomic number (number of protons) for ions, or using the atomic number for neutral atoms.
Calculate the electrons for each species: For example, Na^+ has 11 protons and a +1 charge, so electrons = 11 - 1 = 10; F^- has 9 protons and a -1 charge, so electrons = 9 + 1 = 10; Ne is neutral with 10 protons and 10 electrons; Mg^{2+} has 12 protons and a +2 charge, so electrons = 12 - 2 = 10.
Compare the number of electrons for each species to see which ones have the same electron count.
Identify the species that does NOT have the same number of electrons as the others, which means it is NOT isoelectronic with the rest.
Related Videos
Related Practice
