powdered barium sulfate coated with Pb ,poisoned wid quinoline converts an alkyne to cis-alkene

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A weakened palladium catalyst called Lindlar's catalyst (Pd with CaCO3 and Pb(OAc)2 is very popular . With a weaker catalyst or much milder conditions, it is possible to reduce an alkene without reducing a carbonyl in the same molecule, even if they are conjugated !!!!

See,its a mixture of palladium and barium sulphate.Instead of palladium, you can even use platinum also.