Which of the following represents the correct number of valence electrons and Lewis dot structure for the ion Cl^-?

• A. 8 valence electrons; Cl atom surrounded by 8 dots and enclosed in brackets with a negative sign
• B. 8 valence electrons; Cl atom surrounded by 8 dots without brackets or charge
• C. 7 valence electrons; Cl atom surrounded by 7 dots without brackets or charge
• D. 7 valence electrons; Cl atom surrounded by 7 dots and enclosed in brackets with a negative sign

Answer: (A)

Verified step by step guidance

1. Identify the element in question, which is chlorine (Cl). Determine the number of valence electrons chlorine has in its neutral state. Chlorine is in group 17 of the periodic table, so it has 7 valence electrons.
2. Consider the charge on the ion, which is Cl⁻. The negative charge indicates that the chlorine atom has gained one extra electron, increasing its total valence electrons by 1.
3. Calculate the total number of valence electrons for the Cl⁻ ion by adding the extra electron to the original 7 valence electrons, resulting in 8 valence electrons.
4. Draw the Lewis dot structure by placing 8 dots (representing the 8 valence electrons) around the symbol for chlorine (Cl). The dots should be arranged to show pairs of electrons around the atom.
5. Enclose the entire Lewis structure in brackets and add a negative sign outside the brackets to indicate the charge of the ion, reflecting that it is an anion with an extra electron.