In Hill’s experiment on photosynthesis, Potassium ferric oxalate is used as an acceptor of

In 1937, Robert Hill demonstrated that isolated chloroplasts evolved oxygen in the absence of CO₂ when they were illuminated in the presence of a suitable electron acceptor such as potassium ferricyanide. Ferric compounds are reduced to ferrous compounds by photolysis of water. This is called Hill’s Reaction.