Question

Gas Kinetics Below are some examples of different fragrances. If they were all released simultaneously from the same point in a room 100 feet away from you, which would take the LONGEST for you to smell? Each point on a line structure is a carbon and that carbon has enough H to make four bonds if not shown Likewise, if they were all trapped within a balloon and a hole was poked in the balloon, which smell would you likely smell first? What factor has the largest influence on the rms of a molecule? The compounds responsible for the skunk spray smell are crotyl mercaptan (MW = 90.2 g/mol) and isopentyl mercaptan. If a skunk sprays you on a hot day (42C), crotyl mercaptan has a Urms = 319.8 m/s. If at that temperature it also diffuses 1.09 times faster than isopenty mercaptan, what is the molecular weight of mercaptan (support with work)? Sketch the plot with rms on the x axis of skunk spray (either molecule) at various temperatures.

Answer 1

This question is based on the kinetic theory of gases. Here concept of root mean square velocity and grahms law of diffusion is used.
WWW Gas kinetics ( Fragrances) Fragrance ragrance which will move faster will detect Fiesta Now, Velocity of flageance - 3 RT M Where To Temperature Me Molecular weight. s constant for each fragrance. Therefore Flagrance which have highest molecular will take longer time for you to smell Balloon gas will When a diffuse hole out is from made the in ballon , orifice. Rate of diffuse out l a 1 Malecular weight 25 Thus, fragrance diffuse out with faster loest Molecular weight will and will smell first- Factods largest influence on Rms of molecule (i) Molecular weight (ii) Temperatue.

Molecular weight of ecular Goryl Mercaptan = 90.2 g/mol мея Rate Rate of of diffusion diffusion of of Gotul mecaptan Isopentyl Maceptan . 1.09 t Thus. 1:09. Mol. wt. of Iso pentyl Meceptan Molo wt i of Gotyl Mercaptan rti 1.09- Mol. wt. of TI Isopbently 90.2 T Molecular weight of = 1.1881 + 90.2g Isopentyl Merceptan = 107.167 g TATURTINTINITIATTEOTTI TUTTET Plot of rms on x -axis and Temperature on Y-axis RMS & ST Ta (Rms) ч х? ISTITITETETT 314 L a Like a Uberaad Parabola lunedy sud &