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Question 18N.3.sl.TZ0.a

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Date November 2018 Marks available [Maximum mark: 2] Reference code 18N.3.sl.TZ0.a
Level sl Paper 3 Time zone TZ0
Command term Outline Question number a Adapted from N/A
a.
[Maximum mark: 2]
18N.3.sl.TZ0.a

While heating solid cholesteryl benzoate, Reinitzer discovered the liquid crystal phase.

Outline two observations that he could have made.

[2]

Markscheme

Any two of:

cloudy/foggy/hazy phase «at first melting point» ✔

clear liquid phase «at second melting point/higher temperature» ✔

 

two «different» melting points

OR

new phase observed over a wide temperature range ✔

 

Accept “exhibit both liquid and solid properties at the same time” for M3.

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