The results of either of the two preceding problems can also be applied to the vibrational motions of gas molecules. Looking only at the vibrational contribution to the heat capacity graph for H2 shown in below Figure, estimate the value of ϵ for the vibrational motion of an H2 molecule.
Figure: Heat capacity at constant volume of one mole of hydrogen (H2) gas.Note that the temperature scale is logarithmic. Below about 100 K only the threetranslational degrees of freedom are active. Around room temperature the tworotational degrees of freedom are active as well. Above 1000 K the two vibrationaldegrees of freedom also become active. At atmospheric pressure, hydrogen liquefiesat 20 K and begins to dissociate at about 2000 K. Data from Woolley et al. (1948).
Wednesday, September 21, 2016 Bio 1020 Facilitated Diffusion: Passive Transport Aided by Proteins - In facilitated diffusion, transport proteins speed the passive movement of molecules across the plasma membrane - Channel proteins provide corridors that allow a speciﬁc molecule or ion to cross the membrane - Channel Proteins include • Aquaporins, for facilitated diffusion of water • Ion channels that open or close in response to a stimulus (gated channels) - Passive transport = no energy input required - Tonicity affects passivity of transport - Active transport uses energy to move solutes against their gradients - Facilitated diffusion is still passive bc the solute moves down its concentration gradient and the transport requires no energy - Some transport prote