Copper slowly corrodes to a green mass, a dampened iron nail transforms into red-brown rust - these are chemical changes.
(these; are; chemical changes) Context(these are,List([94, 103))):(a dampened iron nail; transforms; into red-brown rust) Context(a dampened iron nail transforms these are,List([40, 103))):(Copper; slowly corrodes; to a green mass)
these are,List([94, 103)) a dampened iron nail transforms these are,List([40, 103))
these a dampened iron nail Copper
are transforms slowly corrodes
chemical changes
into red-brown rust
to a green mass