95% of LPG sample under consideration should evaporate at a temperature of +2oc. If the evaporation temperature exceeds +2oc then there is a probability that heavier hydrocarbons are present in LPG and if the evaporation temperature is less then +2oc then there is a probability that lighter fractions are more. Significance: This test is intended to find out the presence of heavier hydrocarbons in LPG, which may not readily evaporate. This test is done specially for LPG.
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Why Weathering Test is performed?