Thomas Graham studied the behavior of the diffusion of gases of unequal densities when placed in contact with each other, using air as his control. He wanted to numerically prove how the diffusion of the gas volumes was inversely proportional to the value of the density of the gas, under constant temperature and pressure. The significance of this experiment was that in led to a reevaluation of the concept of the movement of matter, realizing that diffusion dealt with small immeasurable elements of matter, as opposed to large volumes of air, as perceived in the corpuscular theory, shedding light into the study of the behavior and structure of matter.
Graham’s initial objective was to establish a numerical value regarding the gas density and its diffusiveness for ten different gases, establishing that the greater the gas’s density the smaller the value and rate of diffusiveness compared to air. He predicted that gases moved by diffusion when placed together in the form of minute volumes, were the heavier gas would tend to accumulate on one side while the lighter gas displaced towards the denser gas until a uniform mixture was achieved. In light of this, he predicted that if controlling temperature and pressure he would achieve the gases to diffuse and establish a numerical value. However no hypothesis was established based on the limited information at their disposal of matter. However seeing how gases diffused proportionately despite the aperture size, Graham perceived that diffusion dealt with minute particles as opposed to large volumes. The gas’s diffusion volume was achieved once the gas inside the stucco container was entirely replaced by external air, being this new volume the equivalent volume of diffusion. Once established the volume, he used his law of diffusion to provide a numerical value and verify the exactness of his formula. This was achieved by observing the change in height of the level of mercury. The use of a stucco plug channel containers...
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