Hi. I am having a hard to understanding chemistry. currently the problem I'm working on is C2H4+3O2=2CO2+2H20. I need to know the total and exothermic/ endothermic.​

i think is conclusions.i think so

ok whats the question if not i cannot you i need question and need a thing to answer

when the pressure is increased, there will be a shift to the reactants side. decreasing the volume will increase pressure. when you decrease the volume, the gaseous species get more tightly packed of the concentrations of gaseous species increase.

le chatelier's principle says that the system wants to undo this concentration increase so it can decrease pressure.

since the reactants only have 1 mol of gas (only pcl5) and the products have 2 mol of gas (both pcl3 and cl2), it shifts to reactants to decrease concentration, thereby lowering the pressure