Use this guide to facilitate discussion, not just to provide answers. The power of POGIL is in the argument—let the students defend why the tail matters more than the peak.
No, the shape does not change.
"A catalyst does not alter the Maxwell-Boltzmann distribution (the curve does not change). It lowers the activation energy threshold, so a larger fraction of the existing molecules have sufficient energy to react. Temperature changes the shape of the distribution curve itself." Part 4: Common Extension Question 3 – Fractional Distribution Calculations Question: Given that the fraction of molecules with kinetic energy greater than (E_a) is roughly ( e^-E_a / RT ), explain why a reaction with (E_a = 50 \text kJ/mol) proceeds very slowly at 300K but rapidly at 400K. (Use (R = 8.314 \text J/mol·K)). Answer Key Reasoning Students must perform a qualitative calculation to see the exponential effect. Use this guide to facilitate discussion, not just
"The M-B curves for isotopes are nearly identical because mass difference is small relative to absolute mass. However, the effusion rate depends on the inverse square root of mass. Over many stages, this tiny difference in the distribution's average velocity accumulates into measurable separation." Part 6: Common Extension Question 5 – The Effect of a Vacuum Question: The M-B distribution assumes molecules are independent (ideal gas). If you remove half the molecules (create a vacuum), does the distribution shape change? Why or why not? Answer Key Reasoning This is a trick question to test if students confuse distribution with total number . (Use (R = 8