carbon

Carbon (from Latin: carbo "coal") is a chemical element with symbol C and atomic number 6. On the periodic table, it is the first (row 2) of six elements in column (group) 14, which have in common the composition of their outer electron shell. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. There are three naturally occurring isotopes, with 12C and 13C being stable, while 14C is radioactive, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity.
Carbon is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. It is present in all forms of carbon-based life, and in the human body carbon is the second most abundant element by mass (about 18.5%) after oxygen. This abundance, together with the unique diversity of organic compounds and their unusual polymer-forming ability at the temperatures commonly encountered on Earth, make this element the chemical basis of all known life.
The atoms of carbon can be bonded together in different ways: allotropes of carbon. The best known are graphite, diamond, and amorphous carbon. The physical properties of carbon vary widely with the allotropic form. For example, graphite is opaque and black, while diamond is highly transparent. Graphite is soft enough to form a streak on paper (hence its name, from the Greek word "γράφω" which means "to write"), while diamond is the hardest naturally-occurring material known. Graphite is a very good conductor, while diamond has a very low electrical conductivity. Under normal conditions, diamond, carbon nanotubes, and graphene have the highest thermal conductivities of all known materials. All carbon allotropes are solids under normal conditions, with graphite being the most thermodynamically stable form. They are chemically resistant and require high temperature to react even with oxygen.
The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and transition metal carbonyl complexes. The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil and methane clathrates. Carbon forms a vast number of compounds, more than any other element, with almost ten million compounds described to date, which in turn are a tiny fraction of such compounds that are theoretically possible under standard conditions.

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  1. darren@me

    For Sale The Ridge Keycase Forged Ember Matte Carbon Forged BNIB

    Hi all, As per the title, brand new. The photo makes it look orange, but its red. Best Darren
  2. B

    Harbottle Elite Four Fifteen

    The Background: Early last year (January 2023), after copious in depth conversations with Harbottle Audio’s owner & designer Cody Hiebert (collaborates with Nathan Funk to design Funk Audio’s drivers) while being educated by him on their LDCD Guarantee, LDLC & Speaker Competence, 1% Guarantee...
  3. P

    For Sale 2013 Specialized Roubaix Carbon Road Bike with Wheel Upgrade + Accessories

    Hi all, For sale is my 2013 model Specialized Roubaix road bike. I'm not 100% sure of the the size but I'm pretty sure it's a 61 so suitable for a taller rider. The bike is the standard Specialized spec with the addition of : Club Roost R50 deep rim wheels. Schwalbe Ultremo ZX tyres. Selle...
  4. T

    £40bn for Drax carbon capture?

    What am I missing? Drax gets go-ahead for carbon capture project at estimated £40bn cost to bill-payers Scheme to convert biomass units could become one of world’s most expensive energy projects, experts say...
  5. bogart99

    Project RPM5 Carbon turntable

    Project RPM5 Carbon question. I recently sold my RPM5 Carbon and the guy was very happy with it. In passing we have chatted on a couple of other things but he has now told me he thought the belt was stretched and replaced it. Not sure how it stretched over only a couple of years light use but...
  6. H

    Upgrade Pro-Ject Debt III S Cartridge or buy Pro-ject Carbon EVO?

    I'm thinking of upgrading by Pro-Ject Debut III S with a Ortofon Red or Blue OR I just by the new Carbon EVO? A lad at the local Hi-Fi shop told me that I'd hit a ceiling fast with the Debut III S and I should buy the Carbon EVO which is easier to upgrade in the future. Although I really don't...
  7. mattyredsox

    Advice on a new system: bought Audiolab 6000A, Oberon 5, Pro-Ject Debut Carbon Espirit. Possibly adding...

    Hi All. Newbie here, but old human. Kind of what the title says: I need advice on a new system: I've just bought an Audiolab 6000A, Dali Oberon 5s, a Pro-Ject Debut Carbon Espirit. Thinking of adding to it from my old stuff. We've just moved to Geneva, Switzerland from Hiroshima, Japan. My...
  8. Camcroft

    Project Debut Carbon turntable light up

    Just finished playing around with my turntable adding a bit of colour to it.
  9. Reubzen

    Question Pro-Ject Debut Carbon DC - mysterious hum

    Before I get into the problem I’ve been having, my set-up consists of the Pro-Ject Debut Carbon DC with an Ortofon 2M Red cartridge -> Rega Fono Mini A2D preamp -> Pro-Ject Head Box S2 -> Sennheiser HD598 headphones. I had begun to notice a sort of low rumbling hum during lead-ins, between...
  10. R

    Question Which turntable? Rega Planar 3 or Debut Carbon Esprit?

    Evening I'm looking to buy my first turntable and have narrowed my search to either the 2016 Rega Planar 3 with Elys 2 cartridge or the Project Debut Carbon Esprit SB. Can anyone offer any advice on which I should go for? Current set up is an Arcam FMJ A32 Amp through Dynaudio Focus 140...
  11. BritanniaJaf

    Question Best Carbon Mon/Smoke Alarm Wireless - Nest??????

    Guys need some help, just had an engineer out to fix a problem with my boiler and to my horror he advised the CM detector we have is failing close to 30 out of 70 attempts to detect any CM. He advised obviously not to be "cheap" when getting a CM/SA detector and obviously quite right, doing a...
  12. V

    Question Essential III vs Debut Carbon (om10 / 2M-red)

    Essential III vs Debut Carbon (om10 / 2M-red) Hello all, I am in the market for a turntable as my super-budget turntable is not functioning anymore. I did a fare share of research and i narrowed down to the following models from Pro-ject. Essential III 290euro Debut Carbon (om10) 320euros...
  13. IronGiant

    Carbon Dating

    Not sure whether this harks back to the Cretaceous or Jurassic period, I somewhat doubt it was changed at the major service the car is alleged to have had 2 years ago. Any guesses as to how old it really is?
  14. S

    Question What does a mid range analog system sound like?

    This thread is purely subjective and not meant to be a competition. Everyone has different budgets and tastes etc (for example maybe it's more accurate to call this "entry level") But maybe it would be helpful to compare and contrast as well as share advice on upgrades. Here is a video of my...
  15. S

    Turntable not playing songs correctly (Project Debut Carbon Esprit)

    Hope someone can help. Got a new turntable, project debut carbon esprit. Just set it up and some songs are not playing as they should. Seems to be the acoustic guitar track doesn't come through on some songs. It's very faint but the rest of the songs is fine. Based on what i've read online...
  16. B

    Question Pro-Ject Debut Carbon turntable downforce and anti-skating problem

    I'm a turntable novice and I've just got a lovely new Pro-Ject Debut Carbon USB, but I've had some trouble with the initial downforce and anti-skating adjustments and wondered if anyone had any tips. I followed the instructions, and a YouTube video by Henley Designs, which was much clearer, but...
  17. M

    Altered Carbon (Netflix) canceled after season 2

    Netflix Orders ‘Altered Carbon’ Sci-Fi Series From Laeta Kalogridis & Skydance Netflix has picked up Altered Carbon, a futuristic drama series conceived, written and executive produced by Laeta Kalogridis (Avatar, Shutter Island, Terminator Genesis). The project, which has received a 10-episode...
  18. Trash72

    Question Fatman itube 2 carbon edition hum

    Hi guys, First time poster, I have recently been building a set up to allow me to go back to vinyl. I chose the Fatman Carbon edition 2 as my amp as I wanted to be able to play vinyl and my iPod classic and bought one on eBay that was working as expected when I collected it. It came with the...
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