Search results
Results from the WOW.Com Content Network
Boron (5 B) naturally occurs as isotopes 10 B and 11 B, the latter of which makes up about 80% of natural boron. There are 13 radioisotopes that have been discovered, with mass numbers from 7 to 21, all with short half-lives, the longest being that of 8 B, with a half-life of only 771.9(9) ms and 12 B with a half-life of 20.20(2) ms.
The mass difference results in a wide range of ... [55]: 164, 170, 173 A large number of anionic boron hydrides are also known, e.g. [B 12 H 12] 2 ...
In a guideline issued in mid-1966, [49] the U.S. Office of the Federal Coordinator for Meteorology determined that weather data should be rounded to the nearest round number, with the "round half up" tie-breaking rule. For example, 1.5 rounded to integer should become 2, and −1.5 should become −1.
For other isotopes, the isotopic mass is usually within 0.1 u of the mass number. For example, 35 Cl (17 protons and 18 neutrons) has a mass number of 35 and an isotopic mass of 34.96885. [7] The difference of the actual isotopic mass minus the mass number of an atom is known as the mass excess, [8] which for 35 Cl is –0.03115.
This page uses the meta infobox {{Infobox isotopes (meta)}} for the element isotopes infobox.. This infobox contains the table of § Main isotopes, and the § Standard atomic weight.
In chemistry, the whole number rule states that the masses of the isotopes are whole number multiples of the mass of the hydrogen atom. [1] The rule is a modified version of Prout's hypothesis proposed in 1815, to the effect that atomic weights are multiples of the weight of the hydrogen atom. [ 2 ]
The National Credit Union Administration tells consumers to use words for dollars and fractions out of 100 for cents. For example, if your check is for $19.99, you would write it out as ...
The value published can have an uncertainty, like for neon: 20.1797(6), or can be an interval, like for boron: [10.806, 10.821]. Next to these 84 values, IUPAC also publishes abridged values (up to five digits per number only), and for the twelve interval values, conventional values (single number values).