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  1. Well that is an excellent article. +1 And therein goes the material I was going to use for my next post, so I will just pick out the important points that lead to the conclusion I was going to offer. How we got to our modern view of chemistry can be divided into four broad periods. The ancients began to notice that there were many different substances in the world around them. The substances were different because they had different properties. They were hard or soft, some interacted visibly with other substances. Some did not appear to interact at all and some offered protective qualities for other substances. In particular sometimes winemaking went wrong and an unpleasant sour tasting drink was produced instead of acceptable wine. They did not know that wine had turned to acetic acid but their word for vinegar (which is dilute acetic acid) passed down into the Latin word 'acidus' and from there into English as acid. They would also have noticed other properties of acids such as the sting of formic acid in ant bites and the corrosive effect on the skin. It is not known which hero cook spilled animal fat on the fire and roasted it along with wood ash and then found a soapy blob when the result had cooled. But we think this is how middle eastern civilisations discovered soapmaking this way. The ashes provided an alkaline substance which is breaks down fat, something most acids are unable to do. So their for ashes passed into Arabic, Al-Kali and then into English as alkali. Wood (and other plant ) ashes contain what gardeners and farmers call 'potash' which makes a strong alkali with water that we now call potassium hydroxide. So we have the origins of acids and alkalis. The second historical period when humans were able to refine and classify substances, many of which occurred naturally or as with potash by heating or burning and perhaps then adding water. The addition of water was known as slaking; probably the most known and important product was slaked lime or calcium hydroxide, which formed the basis of Roman cement. To obtain this rocks containing calcium carbonate were heated to obtain what was known a quicklime (which we know as calcium oxide). The was the slaked to produce the hydroxide. Calcium carbonate introduces another acid we call carbonic acid, which is important in environmental chemistry. So during this period many names were introduced that were carried forward to the third period which is for next time. Interestingly these time periods have have been 'telescoping'. The first was measured in thousands of years, the second in hundreds of years, and so on.
    2 points
  2. Hopefully your continued exposure to chemical selected names and terms is beginning to bear fruit. So let us carry on with unravelling the history of the subject. The ancient Greeks thought there were four elements, Earth, Water Air and Fire and that all substances were made up from these. In fact they used a different word and the word element came into English from the Latin elementum. Furthermore the concept was very vague in detail and one Greek in particular (Democritus) asked the important question. "What happens if you cut a substance in half, then in half again and in half again and so on ?" He proposed that you would eventually reach a stage where the substance became indivisible and called this piece atomos from where we get the English word atom. This situation continued until the late 17 hundreds when Dalton revived the twin concepts and included the new question "If you can cut substances apart, how can you put them together ?" In his words he described atoms as "All atoms of the same element are alike, globular and all of the same magnitude, but atoms of different elements have different weights." Thus moving atoms from substances to elements and making the distinction. It should be noted that 'weights' were not measured in pounds and ounces or kilogrammes. Hydrogen was give the weight exactly 1 unit and other elements were measured as multiples (including decimal fractions) of this. These weights were called atomic weights. This was a great step forward but it did not explain how or why atoms could be combined in 'fixed proportions' to form substances they could split up. Atoms could not be split up i.e. were indivisible. These insights plus the growing list of elements enabled the first versions of the periodic table to be drawn up. But they were wrong because they placed elements in order of increasing atomic weight, which led to inconsistencies in the chemical properties compared to their placement in 'the table'. The table is called periodic because these properties occur at regular spacing when the elements are placed in the proper order. They had not yet addressed the second question "How can you put them togerther?" Then in 1869 Hofmann, then working in england, coined the English word 'quantivalence'. He introduced the concept of Valency or the combining power of atoms and your next equation from chemical mathematics. Atomic weight = Equivalent weight x Valency. This ushered in the third era in the History of Chemistry and led to a new idea - that of the molecule. At that stage, they still though atoms were 'indivisible' they did not know about electrons, protons and neutrons - that comes in the fourth period up to the present day and was largely invetigated by Physicists. So they quickly determined that oxygen has 2 'hooks' , carbon has 4 'hooks' and nitrogen has '3 hooks' and hydrogen has 1 hook. These hooks were also quickly translated into the ubiquitous chemical stick diagrams we still use today. Here is the diagram for 'ethane' where you can quickly see that each carbon is linked by 4 sticks or hooks and each hydrogen is linked by 1 stickk or hook. This is the 'molecule' of pure ethane.
    1 point
  3. Just when you thought the limits of self-parody had been reached… https://news.sky.com/story/trump-shares-ai-video-of-gaza-vision-featuring-golden-statues-bearded-belly-dancers-and-netanyahu-on-a-sunbed-13317241
    1 point
  4. You haven’t shown us any actual model, which, as both KJW and myself have pointed out, needs to take the form of a metric which is a valid solution to the Einstein equations for a physically reasonable energy-momentum tensor. It is not enough to just present a list of claims; that’s not a model.
    1 point
  5. If you go way, way back, I think they tasted them and they were sour. Your tongue can detect acid this way. There is a bit of the history here: https://pubsapp.acs.org/subscribe/archive/tcaw/12/i03/pdf/303chronicles.pdf
    1 point
  6. Unless you can produce a metric that describes what you are saying, it violates General Relativity. And unless this metric agrees with measured data, it violates reality. Although we don't currently know what dark energy is, any hypothesis needs align with General Relativity, by which I mean that it needs to use the same language as General Relativity.
    1 point
  7. Refer to previous post. It has all needed info
    -1 points
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