CLARIFICATION: Peritectic halts

Peritectic halts

I have had a number of questions about peritectic halts and cooling curves. In all editions of the Atkins' solutions manuals, they get this wrong: there is a halt at the peritectic point on cooling curves (just like for eutectic points). See the example below from Physical Properties of Materials, Second Edition by Mary Anne White. Unfortunately, the slopes of the curves c and e are not correct: since there is very little (Na) (solid) during time period c, and significantly more KNa2(s) during period e, the slope should be more steep for c and less steep for e. The final slope g should be the least steep.

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