2. 2. consider the following reaction occurring in a closed chemical system. assume that this reaction is at equilibrium and that in general the reaction to the right is favored. ch3ch2oh + 3o2 2co2 + 3h2o ∆h = –1,235 kj/mol • what type of chemical reaction is this? • if more ch3ch2oh is added to the system, how will the reactions shift to reach equilibrium again? • if water is extracted from the system, how will the reactions shift to reach equilibrium again? • if heat is removed from the system, how will the reactions shift to reach equilibrium again? • what is the name of the principle that you predict each of these shifts in equilibrium?

1. This is a combustion reaction.

Combustion reactions can happen with the presence of O₂ gas. O₂ reacts with another element or compound and oxidize it. Here ethanol reacts with O₂ and produces CO₂ and H₂O as products. Combustion is also called as burning. 

2. Reaction will shift to right. 

If more CH₃CH₂OH is added to the system, then the amount of CH₃CH₂OH will increase. Then the equilibrium in the system will be broken. To make the equilibrium again, the added CH₃CH₂OH should be removed. To do that system will consume more CH₃CH₂OH to make products which helps to decrease the amount of ethanol. Hence, the reaction will shift to right.

3. The reaction will shift to right.

If the water is extracted from the system, the amount of water will decrease. That means the amount of products decrease. Then the system will try to gain equilibrium by increasing the water. To increase water the forward reaction should be enhanced. Hence, the reaction will shift to right.

4. The reaction will shift to right.

This is an exothermic reaction since it produces heat. If the produced heat is removed, then the system will be cold. To maintain the temperature, system has to increase the amount of heat produced. Then, the forward reaction should be enhanced. Hence, the reaction will shift to right.

5. The Le Chatelier's principle.

Le Chatelier's principle says if a condition changes in a system which was in an equilibrium state, the system will try to gain equilibrium by correcting the changed condition back to normal. Most of industries which make chemicals use this principle

o conteúdo de calor de um sistema é igual à entalpia apenas para um sistema que é constante