Organic Chemistry
(i) Unstable. — It breaks Bredt's Rule; the bridgehead location is in an 8-membered ring.
(ii) Stable. — The alkene (-C=C-) is at the bridgehead location in a 6-membered ring.
(i) Stable. — The alkene (-C=C-) is at the bridgehead location in an 8-membered ring.
(ii) Unstable. — It breaks Bredt's Rule; the alkene is in a bridgehead that is in a 6-membered ring.
(ii) Stable. — The alkene is not at the bridgehead location.
(i) Stable. — The alkene (-C=C-) is at the bridgehead location in a 7-membered ring.
(ii) Unstable. — The trans is in a 6-membered ring.