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