Ohh that makes sense! So basically, c2 can't be a chiral carbon because it has a double bond to another carbon; it doesnt have a hydrogen because it only holds 4 total groups (and a double bond counts as 2).
for C5, past the CH2s, one of them is a carbonyl group (C=O) and the other CH2 leads to the double bonded carbon, making C5 a chiral carbon.
Is my understanding correct?