Which of the following statements is true? a. The rate determining step is always the last step in a reaction mechanism. b. The stability/reactivity principle says that the more stable of two chemicals more reactive c. The reactivity/selectivity principle says that the more reactive of two chemi will be less selective. d. The activation barrier for a reaction is the difference in energy between reac and final products. Which of the following statements is FALSE? a. Optically active solutions always contain chiral molecules.

1. Which of the following is an elementary reaction?A. 2 ClO ---------- Cl2 + O2 Rate = k [ClO] B. N2 + O2 --------- 2 NO Rate = k [N2] [O2]C. NO + O3 --------- NO2 + O2 Rate = k [NO]2D. 2 O3 ------------ 3 O2 Rate = k [O3]

A. Why does catalyst is the factor that has the greatest impact on the rate of reaction in "exhaust from a car engine passes through a catalytic converter changing most of the poisonous nitrogen oxides into nitrogen gas and oxygen gas?" B. Why does concentration is the factor that has the greatest impact on the rate of reaction in "more bubbles appear when a concentrated solution of hydrochloric acid is added to a magnesium strip than when a dilute solution of the acid is added?"

s) For a reaction, the activation energy of the forward reaction is 102 kJ and the activation energy of the reverse reaction is 120 kJ. a. What is the AH of the reaction? b. Is the reaction endothermic or exothermic? c. If a catalyst is added to the reaction, what will happen to each of the following (increase, decrease, or stay the same)? I. Activation energy of the forward reaction Activation energy of the reverse reaction AH of the reaction II. III. IV. Rate of the reaction

A compound A has a half life of 2.4 minutes, and at the beginning, there are 100moles/ L of A. Compound A follows first order decay into two compounds A and B. A. What will be the concentrations of A, B, and C after 7.2 minutes? B. What will be the mole fractions of A, B, and C saftet 4.8 minutes

2. A certain single-substrate reaction is zero order, after 820 s, 40% of the reactants remains. a. Calculate the rate constant of the reaction b. What length of time would be required for the 25% of the reactant to be decomposed?

2. What is the unit of k for each of the following type of reaction? First order reaction a. b. Second order reaction Third order reaction c.

of B → C is rate-determining. ● • Question 9: Write a rate equation for each reaction, given the indicated mechanism. a. CH3CH₂-Br + + OH b. (CH3)3C-Br slow (CH3)3C+ + Br CH,=CH, + H2O + Br -OH fast (CH3)2C=CH₂ + H₂O

For reaction 2Y -> Y2  , where Y represents reactant, the rate constant was found to be second order with respect to Y. Which of the following is true ?   a. The rate constant is dependent on the reciprocal of [Y]. b. The rate of reaction was determined from the equilibrium constant. c. The rate constant of the reaction is equal to equilibrium constant. d. The reaction is an example of a Pseudo first order reaction. -------- For acid base equilibria expression, water is not included in expression because   a. pure liquids are not included in equilibria expression. b. H20 concentration will be assumed constant in equilibria as it will be present in much higher concentration than other molecules in the equilibria. c. H20 concentration will cancel out as it appears in both reactant and product side. d. Kw is so small, hence H20 concentration will be negligible. -----------------  Given below reaction is 1st order reaction with respect to the weak acid and  half life of reaction is 8.9…

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