That was Brian Clegg with the chemistry of calcium carbonate. Now, next week, we smile for the camera. One such property that they were seeking was that of an effective anaesthetic. Having relied for years on opium and alcohol for pain relief, the introduction of diethyl ether as an anaesthetic in was a revelation for the medical profession. However, ether produced undesirable post-anaesthetic effects such as nausea and vomiting.
Chloroform began to be used by British physicians as a better alternative in the late s. But chloroform turned out to be a rather toxic compound in this application. And to find out why, as well as where else this compound is now used in industry join Akshat Rathi in next week's Chemistry in its element. Until then, thank you for listening. I'm Meera Senthilingam. A DNA researcher tells the story of how humans have shaped the evolution of living things on Earth.
Site powered by Webvision Cloud. Skip to main content Skip to navigation. Related audio. Book club — Deep Sniff by Adam Zmith. Book club — Lessons from Plants by Beronda Montgomery. Calcium carbonate. Meera Senthilingam This week, be careful as we're walking on eggshells around Brian Clegg Brian Clegg There is nothing particularly worrying about calcium carbonate.
Davy developed an electrolysis technique, which enabled him to produce the pure form of these active metals, each of which would react rapidly with the atmosphere or with water to revert to the original compound form.
Gimnazija Jesenice Jesenice, Slovenia Teacher: mag. Sodium was discovered by Sir Humphrey Davy in He also travelled a lot and was in our country for a few times Slovenia, Europe. He was amazed by the beauty of our mountains. He especially adored a very small alpine village called Podkoren.
There is an old house with a memorial plate in his honour. In Sir Humphry Davy discovered the element potassium which is why his image was included. The experiment shown at the bottom of the artwork is the reaction of potassium and water forming potassium hydroxide and hydrogen gas. Davy conducted this experiment with Faraday in The 19 silver balls represent the 19 electrons in potassium.
The food on the top right side represents the food containing a high level of potassium. It is formed from the remains of microscopic animals or foraminifera. Marble is a coarse-crystalline, metamorphic rock, which is formed when chalk or limestone are recrystallised under conditions of high temperature and pressure. Calcium carbonate has been used from as early as 40, BC to present day.
The history of calcium carbonate illustrates how we have been able to utilise the unique properties of this mineral in applications ranging from prehistoric cave paintings to modern paper and plastic manufacturing. Other common compounds of calcium include: calcium sulfate CaSO 4 , also known as gypsum, which is used to make dry wall and plaster of Paris, calcium nitrate Ca NO 3 2 , a naturally occurring fertilizer and calcium phosphate Ca 3 PO 4 2 , the main material found in bones and teeth.
Estimated Crustal Abundance : 4. Estimated Oceanic Abundance : 4. Number of Stable Isotopes : 3 View all isotope data. Electron Shell Configuration :. Calcium Previous Isotopes Next. History and Uses : Although calcium is the fifth most abundant element in the earth's crust , it is never found free in nature since it easily forms compounds by reacting with oxygen and water.
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