In the vicinity of the triple point, the vapour pressures of liquid and solid ammonia are respectively given by
$$\eqalign{ & \ln \,\,P = 15.16 - 3063/T \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,and \cr & \ln \,\,P = 18.70 - 3754/T \cr} $$

Where $$p$$ is in atmospheres and $$T$$ is in Kelvin. What is the temperature at the triple point.

A reversible heat transfer demands:

Which among the following relations is/are valid ONLY for reversible process undergone by a pure substance?

The first law of thermodynamics takes the form $$W = - \Delta \,H$$ when applied to :