PE=mgh , gravitational potential energy=mgh.
The potential energy in the microscopic world is the energy used to break the bonds. and thus that is stored in the substance
For instance, for a water to become vapour, you know that the volume is increased largely. With the same amount of molecules, you know that the distance between any two molecules may be lengthened in order to provide a larger volume.
Take water molecules as example again
In chemistry, molecules are bonded with intermolecular forces, (i.e. Van der Waals' Forces).To break the bonds, in other words, to seperate them, energy must be input.
Energy is then converted into their potential energy rather than their kinetic energy.
Hence, gas has a larger potential energy than liquid.
I would think that the product is hydrogen peroxide at a particular temperature or with some kinds of catalase. However, I don't know how to predict it. I just know the reaction by memory. Hope someone can help me.