Please solve these questions thank you!!
18. A catalyst is a substance that decreases the energy of the products in a chemical reaction.
19. For the following reaction, the equilibrium concentrations are: PCt5=0.10 M, PCI3=0.20 M, and Ciz=0.011 M. What is the value of the equilibrium constant?
PC5gPCI3aCIa
A) 45
B) 0.10
C) 0.045
D) 0.022
E) 22
20. The value of the equilibrium
A) The concentrations of reactants and products are equal
C) The concentration of products exceeds the concentration of reactants
D) The concentration of reactants exceeds the concentration of products
E) The reactants are solids
21. In the following gas phase reaction, what is the effect of adding more NO2 to the starting reaction mixture?
2NO2(g) → 2NO(g) + O2(g)
A) It would increase the final quantity of products
B) It would slow the reaction down
C) It would decrease the final quantity of products
D) It would make the reaction more endothermic
E) It would make the reaction more exothermic
22. Ng+Og2NOq For the reaction at equilibrium, if the volume of the container is decreased, the amount of NO present will
A) decrease
B) stay the same
C) increase
D) triple
E) double
23) In an exothermic reaction, heat can be considered a
A) catalyst
B) product
C) rate
D) reactant
E) determinant.