Joseph Black (April 16, 1728~December 6, 1799), UKchemist，physical scientist。Blake's main contribution to chemistry is to first study chemical changes with a balance, creatingQuantitative chemical analysis method。He also used this method to find that this calcined limestone did not gain weight due to the absorption of phlogiston, but lost weight due to the release of gas "fixed gas". He also studied the properties of this gas in many aspects, especially its non combustion supporting property and its ability to be absorbed by caustic soda to reduce its corrosion, which shook the popular phlogiston theory at that time and created a new era of gas chemistry.[1]
In chemistry, Blake studied the mutual conversion process of limestone - quicklime - hydrated lime in detail.In the process, Black weighed the solid substances generated in each intermediate link, and then found "fixed air" in the limestone calcination experiment（carbon dioxide)。Through the combustion supporting experiment of "fixed air", it is determined that it is not combustion supporting gas, and then it is concluded that air is composed of multiple gases;ByCaustic alkaliCompared with whether the weak base releases "fixed air" in the chemical reaction, the conclusion that "the corrosiveness of alkali is not the result of the presence of combustibles" is reached.
Physical field
In physics, Blake clarified the two different concepts of heat and temperature.He proposedSpecific heat capacityThe theory of.Created a method for measuring heatCalorimetry。He also found and explained the "latent heat" in the phase change of the state of matter, and quantitatively determined the latent heat of ice melting and estimated the size of the latent heat of water vaporization, which gave J. Watt great enlightenment on his technical transformation of installing a condenser on a steam engine.
Steam engine manufacturing
BlackieJames Watt They are 6 years older and have been good friends all their lives.In his experimental research on steam, Watt helped him.Watt made instruments for Black, and Black's latent heat theory improved Watt's steam engine（NewcomenFor steam engine, the thermal efficiency of Newcomen steam engine is low, which has left a lot of room for later Watt improvement;But in the subsequent scientific development, the mistakes in Newcomen's design are far more important than its correctness.Scientists provide a theoretical basis by deeply distinguishing and analyzing examples that are familiar to others and drawing scientific conclusions that later people marvel at.This is the earliest example of scientific research and technological invention in human history.
