An alkyne with the molecular formula C6H10 was reduced with H2 and Lindlar's catalyst. Ozonolysis of the resulting alkene afforded formaldehyde and an unbranched aldehyde. What is the IUPAC name of the alkyne that was reduced?

The question is asking for the IUPAC name of an alkyne with the molecular formula C6H10. The alkyne was reduced with H2 and Lindlar's catalyst, which means it was converted into a cis-alkene. This alkene was then subjected to ozonolysis, which breaks the double bond and forms two carbonyl compounds. The products were formaldehyde and an unbranched aldehyde, which means the original alkene must have had a double bond between the first and second carbons.

The unbranched aldehyde must be pentanal, which has five carbons. This means the original alkene was 1-pentene. Since the alkyne was reduced to 1-pentene, it must have been 1-pentyne. Therefore, the IUPAC name of the alkyne that was reduced is 1-pentyne.