The physical properties of CFCs and HCFCs are tunable by changes in the number and identity of the halogen atoms.
In general they are volatile, but less so than their parent alkanes.
A form of radiometric dating used to determine the age of organic remains in ancient objects, such as archaeological specimens, on the basis of the half-life of carbon-14 and a comparison between the ratio of carbon-12 to carbon-14 in a sample of the remains to the known ratio in living organisms. A technique for measuring the age of organic remains based on the rate of decay of carbon 14.
The carbon 14 present in an organism at the time of its death decays at a steady rate, and so the age of the remains can be calculated from the amount of carbon 14 that is left. The cells of all living things contain carbon atoms that they take in from their environment.
The decreased volatility is attributed to the molecular polarity induced by the halides, which induces intermolecular interactions.
Thus, methane boils at −161 °C whereas the fluoromethanes boil between −51.7 (CF).
CDIAC has updated its presentation of data from the NASA Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP), which finds that 2015 was by far the warmest year in the modern temperature record.CDIAC's data holdings include estimates of carbon dioxide emissions from fossil-fuel consumption and land-use changes; records of atmospheric concentrations of carbon dioxide and other radiatively active trace gases; carbon cycle and terrestrial carbon management datasets and analyses; and global/regional climate data and time series.CDIAC provides scientific and data management support for numerous projects including large-scale DOE ecosystem experiments like the Next-Generation Ecosystem Experiments; the Ameri Flux Network, continuous observations of ecosystem level exchanges of CO measurements taken aboard ocean research vessels; and the HIPPO project, which measured and is analyzing the atmospheric carbon cycle and greenhouse gas concentrations from pole to pole over the Pacific Ocean.er et grundstof med atomnummer 6 i det periodiske system med symbolet C.I det periodiske system er det det første (i række 2) af seks elementer i gruppe 14, som har sammensætningen af deres ydre elektronskal til fælles.Det er ikke-metallisk og tetravalent — hvilket vil sige, at det gør fire elektroner tilgængelige til at danne kovalente kemiske bindinger.