Mixed explosive compositions atomic composition

An example of a typical mixed explosive composition is one which contains 60% RDX and 40% TNT, and where the heat of explosion Q has been optimized. In order to calculate the values of Q and V for this composition the oxygen balance and the reaction for decomposition need to be determined. But even before these can be calculated the atomic composition of the mixture must hrst be established. 

When a combustible substance is mixed with air, the mixture will explode only when it is neither too rich nor too lean. The lower explosion limit (LEL) is the minimum volume percent of the substance in air with flammability, which is separated from the upper explosion limit (UEL) by the explosive concentration range. The tabulations in handbooks are based on experimental data, and sometimes derived from estimation methods based on the elemental composition of the fuel as CmEtxOy. Figure 6.11 shows the LEL for the series of normal paraffins and of 1-alcohols versus the number of carbon atoms. There are two ways to plot the results, which show that, for paraffins, the volume percent shows a steeply declining trend, but the weight percent shows a mildly increasing trend. One may conclude that a smaller volume percent of higher paraffin... 

---