01 元素和元素周期表 The number of protons in the nucleus of an atom is referred to as the atomic number, or proton number, Z
The number of electrons in an electrically neutral atom is also equal to the atomic number, Z
The total mass of an atom is determined very nearly by the total number of protons and neutrons in its nucleus
This total is called the mass number, A
The number of neutrons in an atom, the neutron number, is given by the quantity A-Z
原子核内的质子数被称为原子序数,或质子数,Z
一个电中性原子的电子数量也等于原子序数,Z
原子的总质量接近核内质子数和中子数之和
这个总数被称为质量数A
中子在一个原子中的数量,中子数,给出了的数量为A-Z
The term element refers to, a pure substance with atoms all of a single kind
To the chemist the "kind" of atom is specified by its atomic number, since this is the property that determines its chemical behavior
At present all the atoms from Z