When a 1:1 mixture of ethyl propanoate and ethyl butanoate is treated with sodium ethoxide, four Claisen condensation products are possible. Draw the structure(s) of the product(s) that have an ethyl group on the chiral center

attached below

Explanation:

The Four Claisen condensation are grouped into :

Self Claisen condensation is when R = R'

Cross Claisen condensation is when R ≠ R'

attached below are the four Claisen condensation

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.