ionic radius decreases across a period. which ion will have the smaller radius? oxide o - 2 fluoride f - 1
ionic radius decreases across a period. which ion will have the smaller radius? oxide o - 2 fluoride f - 1
Answer
Explanation:
Step1: Recall ionic - radius trend
Ionic radius decreases across a period for isoelectronic species.
Step2: Analyze the ions
Both $O^{2 - }$ and $F^-$ are isoelectronic (have the same number of electrons). Oxygen has atomic number 8 and fluorine has atomic number 9.
Step3: Determine the ion with smaller radius
Since the number of protons in $F^-$ (9) is more than in $O^{2 - }$ (8), the electrons in $F^-$ are more strongly attracted to the nucleus. So, $F^-$ has a smaller ionic radius.
Answer:
Fluoride $F^-$