Question 24: The first-order reaction A -> Products has a half-life of 15.8 min at 30 C and 3.9 min at 90 C. Calculate the activation energy in kJ/mol to three significant figures. The activation energy of this reaction is Check kJ/mol Question 25: A reaction doubles in rate then the tempreature is increased from 35 C to 45 C. Calculate the activation energy in kJ/mol to three significant figures. Ea = Check kJ/mol Question 26: Factor(s) that influence the rate of a reaction but not the rate constant is(are) concentration of products temperature concentration of reactants Check

For the reaction 2N2O(g)2N2(g)+O2(g) the rate constant is 0.066 L/mol min at 565C and 22.8 L/mol min at 728C. (a) What is the activation energy of the reaction? (b) What is k at 485C? (c) At what temperature is k, the rate constant, equal to 11.6 L/mol min?

Compare the functions of homogeneous and heterogeneous catalysts.

Experiments have shown that the average frequency of chirping by a snowy tree cricket (Oecanthus fultoni) depends on temperature as shown in the table. Chirping Rate (per min) Temperature (C) 178 25.0 126 20.3 100. 17.3 What is the apparent activation energy of the process that controls the chirping? What is the rate of chirping expected at a temperature of 7.5C?

In an experiment, a sample of NaClO3 was 90% decomposed in 48 min. Approximately how long would this decomposition have taken if the sample had been heated 20 C higher? (Hint: Assume the rate doubles for each 10 C rise in temperature.)

Would the slope of a ln(k) versus 1/T plot (with temperature in kelvin) for a catalyzed reaction be more or less negative than the slope of the ln(k) versus 1/T plot for the uncatalyzed reaction? Explain. Assume both rate laws are first-order overall.

When formic acid is heated, it decomposes to hydrogen and carbon dioxide in a first-order decay. HCOOH(g) CO2(g) + H2(g) At 550 C, the half-life of formic acid is 24.5 minutes. (a) What is the rate constant, and what are its units? (b) How many seconds are needed for formic acid, initially 0.15 M, to decrease to 0.015 M?

The half-life of tritium, 3H, is 12.26 years. Tritium is the radioactive isotope of hydrogen. (a) What is the rate constant for the radioactive decay of tritium, in y1 and s1? (b) What percentage of the original tritium is left after 61.3 years?

Consider the hypothetical reaction A2(g) + B2(g) 2AB(g), where the rate law is: [A2]t=k[A2][B2] The value of the rate constant at 302C is 2.45 104 L/mol s, and at 508C the rate constant is 0.891 L/mol s. What is the activation energy for this reaction? What is the value of the rate constant for this reaction at 375C?

The hypothetical reaction QR+Xproductswas monitored at 27C as a function of time. The following plots are obtained: (a) Write the rate expression for the reaction. (b) What is the rate constant if the rate of the reaction is 0.29 mol/L min when [ QR ]=[ X ]=1.000M? (c) What is the half-life for the consumption of QR when [ QR ]=0.0866M? (d) If the initial concentration of [ X ]=5.00M, what is [ X ] after 4.7 min?