# Comparing Viscosity: Why C5H11OH is 12x Thicker than C6H14 at 20°C

Chapter 11, Problem 52P

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QUESTION:

Pentanol $$\mathrm{C}_{5} \mathrm{H}_{11} \mathrm{OH} ; \mathcal{M}=88.15 \mathrm{~g} / \mathrm{mol}$$) has nearly the same molar mass as hexane $$(\mathrm{C}_{6} \mathrm{H}_{14} ; \mathcal{M}=86.17 \mathrm{~g} / \mathrm{mol}$$) but is more than 12 times as viscous at $$20^{\circ} \mathrm{C}$$. Explain.

##### Comparing Viscosity: Why C5H11OH is 12x Thicker than C6H14 at 20°C

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Explore the intriguing contrast between Pentanol and Hexane's viscosity at 20 degrees Celsius. Uncover how molecular interactions influence a liquid's 'thickness' and discover why similar molecular weights can lead to vastly different substance properties

QUESTION:

Pentanol $$\mathrm{C}_{5} \mathrm{H}_{11} \mathrm{OH} ; \mathcal{M}=88.15 \mathrm{~g} / \mathrm{mol}$$) has nearly the same molar mass as hexane $$(\mathrm{C}_{6} \mathrm{H}_{14} ; \mathcal{M}=86.17 \mathrm{~g} / \mathrm{mol}$$) but is more than 12 times as viscous at $$20^{\circ} \mathrm{C}$$. Explain.

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Pentanol ($$C_5H_{11}OH$$; $$M$$ = $$88.15 g/mol$$) has nearly the same molar mass as hexane
($$C_6H_{14}; M = 86.17 g/mol$$) but is more than 12 times as viscous at $$20^\circ C$$ because pentanol exhibit
H-bonding whereas hexane exhibit dispersion force.