Chemistrys First Law

The first scientist to demonstrate the existence of a vacuum was Evangelista Torricelli. In 1643, he showed that when a glass tube that was 3 ft. long and about 1 in. in diameter was sealed at one end, filled with mercury, and inverted in a container full of mercury, the mercury in the tube fell to a height of about 30 in. above the level of mercury in the container. Some thinkers remained skeptical, but it was generally accepted that the space between the mercury and the sealed end of the tube was indeed a vacuum. 

Torricelli then turned his attention to how the mercury in the glass tube of his apparatus was supported. The fact that liquids exert a pressure on objects immersed in them inspired him to hypothesize that a sea of air surrounded Earth. He further hypothesized that the air exerted pressure on the mercury in the container and thus supported the mercury in the column. 

Although the idea of an atmosphere that has weight and exerts a pressure on the objects within it seems obvious today, it was a radical theory at the time. To test the effects of the atmosphere, Robert Boyle, one of the period s great scientists, had his talented assistant, Robert Hooke, create a piece of equipment that would revolutionize the study of air. The apparatus was an improved version of a pump designed by the German experimenter Otto von Guericke the pump had a large receptacle in which a partial vacuum could be created. 

Boyle placed Torricelli s setup, known today as a barometer, in the receptacle of the pump and observed the mercury column as he reduced the pressure around it. The height of the mercury decreased as the pressure surrounding the mercury in the container dropped, strongly supporting Torricelli s atmospheric theory. 

Using Hooke s pump, Boyle performed additional studies that verified the idea that air exerted pressure and had weight. Boyle s experiments also led to the important conclusion that air was elastic that is, it could expand and contract. Boyle discovered the fundamental law that bears his name during an investigation into air s elasticity. 

---

Quantitative aspects of chemistry first law of thermodynamics, solution theory, equilibrium, kinetics electrochemistry and redox reactions inquiry and problem solving. 

---