The Thermiate Reaction

This is introductory lecture into Statistical Thermodynamics and provides some basic concepts. The main focus in these lectures are gases because their easier to explain some key concepts of Statistical Thermodynamics. Besides lectures some solved problems will be provided in order to better understand basic concepts.

The Thermite Reaction

Figure 1 - Example of Thermite Reaction

Will start with thermite reaction. Here is the video which demonstrate this chemical reaction. Courtesy of Online Chemistry at OSU. 

Fe₂O₃(s) +2Al(s) →Al₂O₃(s) + 2Fe(s)

In order to detect direction in which reaction goes the thermo-chemical quantity called enthalpy needs to be assessed. Enthalpy is the property of the substance and are tabulated for common substances.

For thermite reaction difference in enthalpy is equal to: 

$$\Delta {{H}_{rxn}}\approx -850\text{ KJ/mol}=-850000\text{J/mol}$$

The reason why enthalpy is negative is because the heat is released and this reaction can be classified as Exothermic Reaction.  When heat is released the temperatures raises and it’s melting solids. We can say that this reaction is good for welding application. 

Figure 2 - Application of thermite reaction in welding of train tracks

In next post we'll talk about some basic thermodynamic terms that are needed in orther to proceed further.