Stimulated by an X-ray beam,chemical elementsin the painting fluoresce, revealing hidden pigments without damaging the artwork.───因为受到X射线的催化作用,油画上的化学元素发出荧光,在没有损坏艺术品的前提下显示出隐藏的画面。 Two newchemical elements, numbers 114 and 116, have been officially recogn...
Define Chemical equations. Chemical equations synonyms, Chemical equations pronunciation, Chemical equations translation, English dictionary definition of Chemical equations. n a representation of a chemical reaction using symbols of the elements to indi
A chemical element is a substance which cannot be decomposed or resolved into simpler substances by ordinary chemical means. Altogether 105 elements are known. Each element consists of one or more atoms with the same number of protons in the nucleus and electrons outside the nucleus. Not all at...
Holmium, Chemical Element HOLMIUM Overview Holmium occurs in Row 6 of the periodic table. The periodic table is a chart that shows how chemical elements are related to each other. Elements with atomic numbers 58 through 71 are known as the lanthanides. The name comes from the element ...
The most recently discovered element is Tennessine, with an atomic number of 117. The reason a more recent discovery can have a smaller atomic number is that atomic numbers are based on the number of protons in a nucleus instead of the order of discovery....
element, emulsion, equation, ester, ether, evaporation, fat, fatty acid, fermentation, fission, foam, formula, fuel, fusion, gas, halogen, hydrocarbon, hydrolysis, inert, inorganic, insoluble, ion, ionic bond, ionization, isomer, isotope, lanthanideorrare-earth element, liquid, litmus test, melt...
That is, all element and group multipliers are assumed to be printed as subscripted numbers. (An exception to this rule exists for *_moiety formulae where pre- and post-multipliers are permitted for molecular units.) (5) Unless the elements are ordered in a manner that corresponds to their...
It is usually best to begin by balancing compounds containing the least abundant element, so we first balance the equation for carbon: C3H8 + O2→3 CO2 + H2O In balancing the oxygen, we see that there is no way that an even number of O2 molecules on the left can yield the uneven nu...
One of two or more atoms having the same atomic number but different mass numbers. [iso- + Greek topos, place (so called because the isotopes of a chemical element occupy the same position in the periodic table of elements).] i′so·top′ic (-tŏp′ĭk) adj. i′so·top′i·cal...
In 1955 the 101st element was named mendelevium in his honor. The concept of sub-atomic particles did not exist in the 19th century. In 1913, English physicist Henry Moseley used X-rays to measure the wavelengths of elements and correlated these measurements to their atomic numbers. He then...