论文部分内容阅读
考点一核素1.核素符号中,左下方的数字表示质子数,左上方的数字表示质量数,质量数=质子数+中子数,在原子中:核电荷数=质子数=原子序数=核外电子数。2.同位素是指质子数相同、中子数不同的原子;同素异形体是指同种元素形成的不同单质(如金刚石与石墨、C60,红磷与白磷,O2与O3)。3.化学变化中原子核不发生变化;不同核素之间转化时原子核发生了变化,不属于化学
Test site a nuclide 1. Nuclide symbol, the lower left of the figure that the number of protons, the upper left of the figure that the mass number, the mass number = the number of protons + neutrons, in the atom: nuclear charge = proton number = atomic number Number of extranuclear electrons. 2. Isotopes refer to atoms with the same number of protons and different numbers of neutrons; allotropes refer to different elements (such as diamond and graphite, C60, red phosphorus and white phosphorus, O2 and O3) formed by the same type of elements. 3. Chemical changes in the nucleus does not change; between different radionuclides when the nuclear changes have taken place, do not belong to the chemical