HW 11-3 Reaction profile diagrams ENERGY

Reactants start at 0 energy. Key Features: Y-axis = ENERGY X-axis = Reaction Progress (similar to time) Reactants start at 0 energy. TS = HIGHEST energy point at the TOP of the activation barrier. Old bonds being BROKEN new bond being FORMED. ΔE = energy PRODUCTS – REACTANTS; Ea = Δ between R and TS

1A AND 1B) EXOTHERMIC RXN PRODUCTS ARE LOWER IN E THAN REACTANTS; ENDOTHERMIC REACTANTS ARE LOWER IN E THAN PRODUCTS

A) Ea = +10 kJ/mol ∆E = -10 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +10 kJ/mol ∆E = -10 kJ/mol

A) Ea = +10 kJ/mol ∆E = -10 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +10 kJ/mol ∆E = -10 kJ/mol

A) Ea = +30 kJ/mol ∆E = +10 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +30 kJ/mol ∆E = +10 kJ/mol

A) Ea = +30 kJ/mol ∆E = +10 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +30 kJ/mol ∆E = +10 kJ/mol

A) Ea = +25 kJ/mol ∆E = -30 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +25 kJ/mol ∆E = -30 kJ/mol

A) Ea = +25 kJ/mol ∆E = -30 kJ/mol ENERGY (kJ/mol) RXN PROGRESS A) Ea = +25 kJ/mol ∆E = -30 kJ/mol

LINK TO NI3 Reaction ENERGY (kJ/mol) RXN PROGRESS

RXN PROGRESS Decomposition of NI3: Small Ea (Touch of a feather sets off reaction Large ∆E (Large amount of E released) ENERGY (kJ/mol) RXN PROGRESS

HW 11-3 catalysts #5) A catalyst is a substance that SPEEDS UP the rate of a chemical reaction without itself BEING CONSUMED IN THE RXN.

Time- Lapse of CoCl2 catalyzed rxn of tartrate and h2O2 HW 11-3, Part 6, # REACTION DOES NOT OCCUR AT OBSERVABLE RATE WITHOUT CATALYST Initial During Final Link #6 Catalyst

Time- Lapse of CoCl2 catalyzed rxn of tartrate and h2O2 HW 11-3, Part 6, # Link #6 Catalyst Initial During Final Catalyst (CoCl2) accelerates the rate of reaction without itself being consumed in the reaction

11-3, #7 catalyst in Ozone decomposition rxn Cl is the catalyst; It speeds up the breakdown of ozone, but is not used up in the reaction.

Higher % successfully jumped lower height barrier 1 1/5 x100 = 20% 4 4/5 x100 = 80%

HW 11-3, #9: Catalysts accelerate reactions without being consumed by lowering the energy of activation Lower Ea = Faster rxn A) ∆E does NOT change B) Ea is SMALLER C) LOWERING Link to collision theory animation

Hw 11-3, #10A – What is an enzyme? A) Enzymes are biological catalysts that speed up the rate of chemical reactions inside your body.

Hw 11-3, #10B – Why are enzymes important? B) Enzymes control the rates of virtually all important chemical reactions in your body.

Picture of enzyme catalyst Active site Enzyme link HW 11-3, #10

Active site

Enzyme active site will only accept specific substrates reactants with correct size and shape