Select the catalyst used in hydrogenation of ethene.
Show Hint
"Finely divided" is a crucial keyword for heterogeneous catalysts! Crushing the metal into a fine powder drastically increases the surface area, exposing more active sites and massively increasing the reaction rate.
Step 1: Name the reaction.
Adding hydrogen across a C=C double bond is catalytic hydrogenation.
Step 2: Recall the usual catalysts.
The common metals for this are nickel, palladium and platinum. Iron is for ammonia making and $\text{MnO}_2$ is for other jobs.
Step 3: Pick from the list.
Finely divided nickel gives a large surface and works well here.
\[ \boxed{\text{Ni (finely divided)}} \]