Question

get it? explain why an atom of iodine tends to react to gain one electron.

Explanation:

Iodine has 7 valence electrons. Atoms tend to achieve a stable electron configuration (like noble gases). By gaining one electron, iodine can have 8 valence electrons (a full outer shell), which is more stable.

Answer:

Iodine has 7 valence electrons. Gaining one electron gives it a full outer shell (8 valence electrons), achieving a stable electron configuration like noble gases.