CHEM 111 Lecture Notes - Lecture 36: Thermodynamics, Calorimeter, Internal Energy

65 views2 pages

Document Summary

Wet lab this friday (goggles and closed-toed shoes required) Online and written homework due mon at 5pm. Writing assignment audience: your peers next week: only class is monday. In thermodynamics, the energy change for a system is defined as the sum of heat and work. When work is done by the system deltav > 0, w < 0 change in volume = positive, work = negative always view things from the point of view of the system. Energy: heat + work deltau = q + w. Combust h2, ch4, c2h6, and c4h10 least to most energy. C4h10 + (13/2)o2 5h2o + 4co2 molar ratios = ok to use fractions. Amount of energy required to change t depends on heat capacity,c q = cdt. Heat capacity is extensive (it depends on the amount of stuff) q = ncmdt. Heat and work, q & w, are like credit cards or checks: they are ways of moving the money.