{HEAD ~ Approximately 1 ml} of acetaldehyde, or {TAIL ~ any other aldehyde}, is added to the mixture 
of
{ HEAD ~ Approximately 1 ml } of acetaldehyde , or { TAIL ~ any other aldehyde } , is added to the mixture
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH