CaCO3 (s)   CaO (s) + CO2 (g) 7:16 #14 ANALYZE : question asks for a equilibrium shift resulting from a pressure change. THEORY: LeChatelier : Increasing pressure goes to side of least moles OF GAS. APPLY: the answer is choice 2, there are no gasses on the left, increasing pressure goes there. CaCO3 (s)   CaO (s) + CO2 (g) 7:16 #15 ANALYZE: Temp is increased changed on a system at equilibrium. THEORY: Increasing temp reverses an exothermic reaction, forwards an endothermic one. APPLY. This reaction is endothermic (heat is written on the left) 2HBr + 72.7 kJ   H2 + Br2 HEAT -2X +X +X choice 1 Increase T, heat enters on left, EQ shifts to the right,

Increase N2, enters on left, EQ shifts to the right, 7:16 #16 ANALYZE : question asks for a equilibrium shift resulting from a increase of N2 change. THEORY: LeChatelier : Increasing on one side shifts to the opposite side. APPLY: N2 is on the left. Increasing it shifts to the right. N2 (g) + O2 (g)  2 NO (g) WHAT THE SYSTEM WILL DO AFTER STRESS IS ADDED. -X -X + 2X Increase N2, enters on left, EQ shifts to the right, 7:22 #34 ANALYZE : about an equilibrium pressure increase stress. THEORY: LeChatelier : Increasing pressure drives to the side of least moles OF GAS. APPLY: moles on each side are equal, no effect! Ans C no change N2 (g) + O2 (g)  2 NO (g) 1 mole + 1 = 2 moles

2 H2 (g) + O2 (g) 2 H2O (g) + HEAT 7:22 #35 ANALYZE : Heating a systemat equilibrium. THEORY: Heating and exothermic reaction reverses it. APPLY: This reaction will be reversed as you are heating exo reaction, heat enters on the right and shifts left. 2 H2 (g) + O2 (g) 2 H2O (g) + HEAT +2X +X - 2X : choice#4 HEAT INCREASING T, heat enters on RIGHT, drives (LEFT). 7:22 #39 ANALYZE :Common Ion Effect, adding Cl-. THEORY: LeChatelier : on right shifts left . APPLY: In this reaction, Cl- enters on right, reaction shifts LEFT. AgCl(s) (g)   Ag+ (aq) + Cl- (aq) +2X -X - X : choice #2 INCREASING Cl- , enters RIGHT and shifts LEFT.

7:19 #9 ANALYZE: A + B  C + energy IS EXOTHERMIC, heat on right, BEING GIVEN OFF (EVOLVED). THEORY: In an EXOTHERMIC REACTION the products have LESS POTENTIAL ENERY content then the REACTNTS, the rest is lost from the reaction as heat. APPLY: In the reaction kinetics energy graph, the products will be at a LOWER level than reactants. CHOICE 2 A + B C REACTANTS PRODUCTS

7:19 #10 ANALYZE :Potential energy diagram THEORY: The products are at lower energy level in an exothermic reaction. APPLY: In the diagram below, the products are at a lower energy level than the reactants, the difference is evolved as heat (kinetic energy). The reaction loses potential energy as the kinetic energy of heat. A + B AB REACTANTS PRODUCTS

A 7:20 #16 and 17 ANALYZE : Given a potential energy graph THEORY: If the products are at a higher energy level than the reactants, the reaction is ENDOTHERMIC, heat is stored in the products as potential energy. APPLY: The products are at a higher level in this graph, ENDOTHERMIC and energy is gained (absorbed) by the system. ACTIVATED COMPLEX FORWARD ACTIVATION ENERGY A PRODUCTS ANSWER: 16 IS ARROW A, FORWARD ACTIVATION. 17 IS ENDOTHERMIC AND HEAT IS ABSORBED CHOICE 4 REACTANTS