Chapter 4, Problem 4.24P

Interpretation Introduction

Interpretation:

The phase diagram for ${\text{NH}}_{\text{3}}{\text{/N}}_{\text{2}}{\text{H}}_{\text{4}}$ system has to be sketched.

Concept introduction:

A state of matter that is uniform throughout in chemical composition and physical state is known as phase.

Phase diagram is a graphical representation of all the equilibrium phase as a function of temperature, pressure and composition.

A mole fraction of a molecule in a mixture is the ratio of number of moles of particular molecule to the sum of number of moles of all molecules in the mixture. Equation for mole fraction of a molecule in a mixture of three molecules (A, B and C) is,

  $\text{molecule}\text{fraction}\text{of}\text{A,}\text{(}{\text{χ}}_{\text{A}}\text{) }\text{=}\frac{\text{numbers}\text{of moles of}\text{molecule A}{\text{(n}}_{\text{A}}\text{)}}{\text{total number of moles}{\text{(n}}_{\text{A}}{\text{+n}}_{\text{B}}{\text{+n}}_{\text{C}}\text{) }}$

A eutectic mixture is a mixture of two or more phases at a composition that has the lowest melting point and it is where the phases simultaneously crystallize from molten solution.