a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel 相似短语 atomic number 42phr. 【化学】原子序号42钼 atomic number 2phr. 原子量2;氦 atomic No 42 (Mo)钼 atomic numbern.[化]原子序数(指元素在周期表中按次序排列的序号) ...
1947.: ‘Technetium: The element of atomic number 43’, Nature (Lond.) 159 , 24 pp.Technetium: the element of atomic number 43 - unknown authors - 1947Perrier, C. and Segre, E. 1947.: `Technetium: The element of atomic number 43', Nature (Lond.) 159, 24 pp....
The electron mass is about 1825 times smaller than the proton mass and, therefore, can be neglected in calculating the mass number. For any element, the mass number is equal to the atomic weight rounded off to the nearest integer value. The proton has a positive charge that is equal in ...
an element is a substance , all of ___ atoms have the same atomic number为什么选whose ? 请高手讲讲..相关知识点: 试题来源: 解析 首先句子后面是作定语的,由主句可以知道,修饰的是主语element.因为atoms是原子的意思,对于元素来说,逻辑关系自然是“元素里的原子”,所以element和atoms具有从属关系,用whose...
34 An element has an atomic number of 4.Which statement about this element is correct?A A It forms ions by losing electrons. B It has four occupied electron shells in each of its atoms. C It is an unreactive gas at room temperature and pressure. D It is found in Group IV of the ...
How do I interpret the element boxes? Located right above the Englishname for each element, the largest letters represent itschemical abbreviation. The largest number is the element’satomic number. Other information in the box includes the element’s electron configuration, electronegativity, oxidation...
A typical element of this group is a 3 × 3 unitary matrix with determinant +1. To establish the group structure or symmetry of a Hamiltonian one should find, on the one hand, operators that commute with it and show, on the other, that these operators are the infinitesimal generators of...
5. Element has no stable nuclides. The value enclosed in brackets, e.g. [209], indicates the mass number of the longest-lived isotope of the element. However three such elements (Th, Pa, and U) do have a characteristic terrestrial isotopic composition, and for these an atomic weight is...
Since La is the heaviest element in LLTO and the image contrast increases with the atomic number28,31,32, the arrays of darkest, largest spots in this <110 > p-oriented grain correspond to the La-rich layer, and the arrays of lighter spots located halfway between two La-rich layers...
Silveris a transition metal with element symbol Ag and atomic number 47. The element is found in jewelry and currency for its beauty and value and in electronics for its high conductivity and malleability. Silver Basic Facts Atomic Number:47 ...