- #1
osaka
- 8
- 0
I have a problem with MgO(s).
Mg(s) → Mg(g) Heat of sublimation = +148 kj
½O2(g) → O(g) Bond dissociation = +249 kj
Mg(g) → Mg2+(g)+ 2e- IE1+IE2= +2201 kj
O(g)+2e- → O2- EA= +737 kj
look at the EA in peiodic table O(EA= -141 kj).
When O charged 2e- it seems to be like F(EA=-328 kj) charged 1e-.
it should be - not +.
but Why EA of O=+737kj ?
Mg(s) → Mg(g) Heat of sublimation = +148 kj
½O2(g) → O(g) Bond dissociation = +249 kj
Mg(g) → Mg2+(g)+ 2e- IE1+IE2= +2201 kj
O(g)+2e- → O2- EA= +737 kj
look at the EA in peiodic table O(EA= -141 kj).
When O charged 2e- it seems to be like F(EA=-328 kj) charged 1e-.
it should be - not +.
but Why EA of O=+737kj ?