Mercury-in-glass thermometer ushered in a new era of accuracy and precision in thermometry, and is still to this day regarded as one of the most accurate thermometers available. The thermometer was used by the originators of the Fahrenheit and Celsius scales. Anders Celsius, a Swedish scientist, devised the Celsius scale, which was described in his publication "The origin of the Celsius temperature scale" in 1742. Celsius used two fixed points in his scale: the temperature of melting ice and the temperature of boiling water. This wasn't a new idea, since Isaac Newton was already working on something similar. The distinction of Celsius
Krafft temperature Krafft temperature Krafft temperature is defined as the minimum temperature to form micelles. It is named after German chemist Friedrich Krafft. Below the Krafft temperature, there is no value for the critical micelle concentration (CMC), i.e. micelles cannot form. The Krafft temperature is a point of phase change below which the surfactant remains in crystalline form, even in aqueous solution. Visually the effect of going below the Krafft point is similar to that of going above the cloud point, with the solution becoming cloudy or opaque due to the surfactant molecules undergoing flocculation. Surfactants in such a crystalline state will