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Thermal conductivity of liquid water versus temperature: qualitative trend. How does the thermal conductivity (k) of water change as temperature rises across the practical engineering range? Choose the most correct qualitative statement.

Difficulty: Easy

remains same
decreases
increases
may increase or decrease depending upon temperature

Correct Answer: may increase or decrease depending upon temperature

Explanation:

Concept
Liquid water exhibits a non-monotonic variation of thermal conductivity with temperature: k can increase over some ranges and decrease over others due to changing molecular interactions.

Conclusion
The safest, broadly correct statement is may increase or decrease depending upon temperature.

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