A first order reaction in solution is run twice, from…

Quizzes
A first order reaction in solution is run twice, from the same starting concentration, and followed by measuring the concentration of the reactant. At 300 K, it takes 36.0 min for 25 per cent of the reactant to be used up. At 320 K, the same 25 per cent is used up in only 12.0 min. Assume that the activation energy and the pre-exponential factor do not change between the two temperatures, and take R = 8.314 J K⁻¹ mol⁻¹. What is the activation energy of the reaction, in kJ mol⁻¹, to the nearest integer?

ChemistryHardHigh School (11–12)Chemical Kinetics › Temperature, the Arrhenius Equation and Collision Theory JEE Advanced JEE Main

Created by StemPy Lab

A first order reaction in solution is run twice, from the same starting concentration, and followed by measuring the concentration of the reactant. At $300\ \text{K}$ , it takes $36.0\ \text{min}$ for $25$ per cent of the reactant to be used up. At $320\ \text{K}$ , the same $25$ per cent is used up in only $12.0\ \text{min}$ . Assume that the activation energy and the pre-exponential factor do not change between the two temperatures, and take $R = 8.314\ \text{J K}^{-1}\ \text{mol}^{-1}$ . What is the activation energy of the reaction, in $\text{kJ mol}^{-1}$ , to the nearest integer?

Type your answer as a number (a decimal point is allowed). A wrong answer may cost marks.

← All Quizzes

← Two reactions are run side by side at the same temperature, in separate flasks. X is zero order, so it is used up at a steady rate until none is left. Y is first order. Each reactant starts at 0.800 mol L⁻¹, and in these runs both have a half-life of 20.0 min. The graph shows the concentration of each reactant against time, with the two curves crossing at 20.0 min. Both runs are followed for 40.0 min. Take ln 2 = 0.693. Which of the following statements are correct?Methyl acetate is hydrolysed in dilute hydrochloric acid at 298 K: CH₃COOCH₃ + H₂O → CH₃COOH + CH₃OH. Water is in large excess and the acid is a catalyst, so the reaction is pseudo first order in the ester. At different times, a 5.00 mL portion of the mixture is taken out, cooled in ice and titrated with the same sodium hydroxide solution. The titres are 21.4 mL at the start, 26.8 mL after 30.0 min, and 44.2 mL once the reaction is complete. Take ln 2 = 0.693. What is the half-life of the ester, in min, to the nearest integer? →

More onChemical Kinetics › Temperature, the Arrhenius Equation and Collision Theory

Discussion (0)

Loading…