Are all combination reactions also redox reactions?

If not, please give an example. Thanks!

1 Answer
Dec 27, 2017

Nope .

Not all combination reactions are redox , some are however , like
3Fe + 20_2 -> Fe_3O_4
oxidation number of iron changed from 0 to 2 & 3 and for oxygen it changed from 0 to -2

but others are not

CaO + H_2O -> Ca (OH)_2
oxidation numbers of each element remain constant .
Ca->+2
H->+1
O->-2