called endothermic reaction is any reaction that absorbs heat.
In the video we see the reaction between two solid compounds: barium hydroxide and ammonium nitrate.
The reaction produces barium nitrate, ammonia and water ... and absorbs large amounts of heat, while frozen layer of water left on the wood and the "sticks" to the flask.
Ba (OH) 2 .8 H 2 O + 2 NH 4 NO 3 → Ba (NO 3 ) 2 + 2 NH 3 + 10 H 2 O DH = 80.3 kJ
In this reaction there is a large increase in entropy: we went from 3 moles to 13 moles and solid phase-in substances in solution. This increase of entropy means that the process is spontaneous, but the enthalpy of the process is not favorable. The spontaneity of a chemical reaction is given by the change in Gibbs free energy
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