When the glycerol is heated with the oxalic acid at the temperature of 100 to 110 degrees celsius then formic acid is produced as one of the products and the elimination of water. At the higher temperature of 260 degrees Celsius to 280-degree Celsius, the oxalic acid, as well as the glycerol, reacts with each other to produce allyl alcohol which is also produced via the decarboxylation and the elimination of water. A projection formula is a two-dimensional representation of what actually is a three-dimensional molecule. Such a formula resembles the structural type in that it consists of symbols representing the atoms of constituent elements connected to each other by the dashes or the curves that stand for the chemical bonds. Therefore the methane molecule is characterised by a tetrahedral disposition of the four chemical bonds that take around the carbon atom. This is conveniently represented by the projection formula.