Physical Chemistry , 1st ed.

Equation 2.30 means we can substitute Cpin the previous equation, so we get dHCpdT and integrate to get the total change in ent ...

either side are fixed, it should be understood that the gas experiences a drop in pressure as it is forced from one side to the ...

For an ideal gas,JTis exactly zero, since enthalpy depends only on tempera- ture (that is, at constant enthalpy, temperature is ...

the pressure drops the temperature goes up: it gets hotter upon expansion! At some lower temperature, the Joule-Thomson coeffici ...

temperature, until the temperature drops so low that it condenses into a liquid. Liquid nitrogen and oxygen are commonly prepare ...

variables. (Other derivatives have also been expressed as partial derivatives.) Since dHdqp, we can substitute on the left side ...

Recall that, for an adiabatic process, dUdw because heat is exactly zero. From equation 2.21, we also know that dUCVdT+  U V ...

987 J(1 mol)12.47 mo J lK T T79.1 K With an initial temperature of 273.15 K, the final temperature is about 194 K. Fo ...

We can rearrange the equation relating volumes and temperatures above to get V V f i    T T f i  (2.46) It can be shown ...

H 2 O can exist at 0°C as either a solid or a liquid. Because there is no T,equa- tion 2.9 does not apply. Instead, the amount ...

The heat involved in the reverse process,condensation,can also be calculated with equations 2.52 and 2.53 with the understanding ...

has an unusually large heat of vaporization for such a small molecule. This is caused by the strong hydrogen bonding between wat ...

for 25.0°C. To indicate that the energy change is meant to imply standard con- ditions, a ° superscript is attached to the symbo ...

of a formation reaction, called the enthalpy of formationor (more loosely) the heat of formation.As an example, ^12 N 2 (g) + ...

Reaction a is the reverse reaction for the formation of Fe 2 O 3 ; therefore, the change in enthalpy for a is fH°[Fe 2 O 3 ]. ...

If the standard enthalpy of formation of glucose is 1277 kJ/mol, what is the rxnH° for this process? You will need to get fH° ...

If the chemical process occurs isothermally, then by assuming the gases in- volved are acting ideally, d(pV) d(nRT) dnRT wher ...

process that occurs at a temperature different from that cited by available data (usually 25.0°C). In addition to Hat 25.0°C, w ...

H 2 (393.5 + 0) (110.5 + 241.8) kJ H 2 41.2 kJ Finally, the products of the reaction need to be brought to 500 K; the h ...

This is the reverse of the reaction for glucose oxidation/metabolism. By Hess’s law, the enthalpy change of this reaction is the ...