The variation of Newtonian viscosity with temperature

As we see, a t)rpical liquid has A - 4.8 and B 500 K this means a viscosity of aroimd 0.8 mPa.s at room temperature (20 °C) has a temperature variation of viscosity of -1.34% per degree Celsius. A liquid with a higher viscosity might have say A = -10 and B = 3000 K, which would give a room-temperature viscosity of around 1.7 Pa.s, and a viscosity-temperature sensitivity of - 7.84%/°C. On the other hand, a lower-viscosity liquid fitting this equation might have A = - 3.8 and B = 100 

K this would give a viscosity of 0.35 mPa.s (similar to petroleum) and a temperature sensitivity of only around - 0.27%/°C. In a severe winter diesel oil is said to freeze, thus causing severe problems for transportation. In fact, all that happens is that the viscosity increases to levels where the pumps cannot operate, thus stopping the flow. 

Water over the range 0 -100 °C fits a slightly modified form of the Andrade law, viz. logic 7=A + B/(C-7), with A = - 4.5318, B = - 220.57 K and C = 149.39 K, and at room temperature water changes viscosity at a rate of - 2.54% per degree Celsius, [5]. This means that to perform reasonably reproducible experiments on water-based liquids, we should be careful to control the experiment to within 1 °C. 

---