Q. ${Na}_{2}O,\ MgO,Al_{2}O_{3}\ and\ {SiO}_{2}\$have heat of formation equal to $- 416, - 602, - 1676\$and $- 911\ kJ\ mol^{- 1}$ respectively. The most stable oxide is
A) ${Na}_{2}O$
B) $MgO$
C) $Al_{2}O_{3}$
D) ${SiO}_{2}$
Explanation
(b)
The oxide having maximum heat of formation per oxygen atom (thus energy needed to break one $M - O$ bond will be highest) will be most stable.
MgO is most stable oxide among $Na_{2}O,\ SiO_{2},\ Al_{2}O_{3}$ and MgO.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.