Question

which of the following elements is correctly matched with the number of electrons it needs to become stable? select one: a. sulfur (s) .. 6 b. hydrogen (h) .. 2 c. chlorine (cl) .. 1 d. aluminum (al) .. 3

Explanation:

Step1: Analyze Sulfur's valence electrons

Sulfur has 6 valence electrons. To reach a stable octet, it needs $8-6=2$ electrons, not 6.

Step2: Analyze Hydrogen's valence electrons

Hydrogen has 1 valence electron. It only needs 1 more electron to fill its 1s orbital (stable duet), not 2.

Step3: Analyze Chlorine's valence electrons

Chlorine has 7 valence electrons. To reach a stable octet, it needs $8-7=1$ electron.

Step4: Analyze Aluminum's valence electrons

Aluminum has 3 valence electrons. It typically loses these 3 electrons to become stable (rather than gaining 5), so it does not need 3 electrons to become stable.

Answer:

c. Chlorine (Cl) .. 1