Standard temperature 246 substance from igniting

Table 3-10 gives proof of the above-made remarks. It originates from the same comparative study cited in section 3.3.3. Only in the case of 6 out of 24 substances the ignition temperatures published vary within the range, which is experimentally permitted according to standard DIN 51794. 

The absolute value of a proportional error depends upon the amount of the constituent. Thus a proportional error may arise from an impurity in a standard substance, which leads to an incorrect value for the molarity of a standard solution. Other proportional errors may not vary linearly with the amount of the constituent, but will at least exhibit an increase with the amount of constituent present. One example is the ignition of aluminium oxide at 1200°C the aluminium oxide is anhydrous and virtually non-hygroscopic ignition of various weights at an appreciably lower temperature will show a proportional type of error. 

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