State the second law of thermodynamics.

9.42 Why is enthalpy generally more useful than internal energy in the thermodynamics of real world systems?

9.11 Analyze the units of the quantity (pressurevolume) and show that they are energy units, consistent with the idea of PV-work.

The second law of thermodynamics is sometimes paraphrased as: you can't break even. Explain. Because energy cannot be created out of nothing. Because some energy is lost in all energy transactions. Because some energy is gained in all energy transactons.

A pot of cold water is heated on a stove, and when the water boils, a fresh egg is placed in the water to cook. Describe the events that are occurring in terms of the zeroth law of thermodynamics.

In which of the following systems is(are) work done by the surroundings on the system? Assume pressure and temperature are constant. a. 2SO2(g)+O2(g)2SO3(g) b.CO2(s)CO2(g) c. 4NH3(g)+7O2(g)4NO2(g)+6H2O(g) d.N2O4(g)2NO2(g) e.CaCO3(s)CaCO(s)+CO2(g)

Which of the following processes will lead to a decrease in the internal energy of a system? (1) Energy is transferred as heat to the system; (2) energy is transferred as heat from the system; (3) energy is transferred as work done on the system; or (4) energy is transferred as work done by the system. (a) 1 and 3 (b) 2 and 4 (c) 1 and 4 (d) 2and3

The first law of thermodynamics is sometimes stated You cant win and the second law is stated similarly as You cant even break even. Explain how these two statements can be considered apt though incomplete viewpoints for the first and second laws of thermodynamics.

Coal is used as a fuel in some electric-generating plants. Coal is a complex material, but for simplicity we may consider it to be a form of carbon. The energy that can be derived from a fuel is sometimes compared with the enthalpy of the combustion reaction: C(s)+O2(g)CO2(g) Calculate the standard enthalpy change for this reaction at 25C. Actually, only a fraction of the heat from this reaction is available to produce electric energy. In electric generating plants, this reaction is used to generate heat for a steam engine, which turns the generator. Basically the steam engine is a type of heat engine in which steam enters the engine at high temperature (Th), work is done, and the steam then exits at a lower temperature (Tl). The maximum fraction, f, of heat available to produce useful energy depends on the difference between these temperatures (expressed in kelvins), f = (Th Tl)/Th. What is the maximum heat energy available for useful work from the combustion of 1.00 mol of C(s) to CO2(g)? (Assume the value of H calculated at 25C for the heat obtained in the generator.) It is possible to consider more efficient ways to obtain useful energy from a fuel. For example, methane can be burned in a fuel cell to generate electricity directly. The maximum useful energy obtained in these cases is the maximum work, which equals the free-energy change. Calculate the standard free-energy change for the combustion of 1.00 mol of C(s) to CO2(g). Compare this value with the maximum obtained with the heat engine described here.

One statement of the second law of thermodynamics is that heat cannot be turned completely into work. Another is that the entropy of the universe always increases. How are these two statements related?