This investigation looks at rates of reaction by using the reaction between oxalic acid in the rhubarb and potassium Manganate VII.
As described, the investigation looks at concentration and surface area but temperature would be an easy addition.
Rhubarb! Rhubarb (demonstration version)
Rhubarb Rhubarb – Experiment Guide
Rhubarb Rhubarb – Teacher’s Guide
Rhubarb Rhubarb – Technician’s Guide
Rhubarb Rhubarb – Risk Assessment
Image by Dieter Weber – Used under a Creative Commons License CC BY-SA 3.0
