1,2,3 are H atoms attached to three different C atoms, H at 2 is most acidic but I am not sure which H is least acidic, is it 1 or 3 ,
H at 1 has double bonded oxygen at nearby C and H at 3 has one Singly bonded O and 1 doubly bonded oxygen in 2 and 4 bonds away from it, I guess Least acidic is H at 1 !
What is the correct order?