Atoms, the smallest particles of matter that retain the properties of the matter, are made of protons, electrons, and neutrons. |
原子——最小的能保留物质特征的粒子——是由质子,中子和电子组成的。 |
Protons have a positive charge, Electrons have a negative charge that cancels the proton's positive charge. |
质子带正电荷。电子带负电荷,这就抵消了质子的正电荷。 |
Neutrons are particles that are similar to a proton but have a neutral charge. |
中子是类似于质子的粒子,但不带电荷。 |
There are no differences between positive and negative charges except that particles with the same charge repel each other and particles with opposite charges attract each other. |
除了同种电荷互相排斥,异种电荷互相吸引之外,正电荷和负电荷没有区别。 |
If a solitary positive proton and negative electron are placed near each other they will come together to form a hydrogen atom. |
当一个带正电的质子和带负电的电子靠得很近,它们会聚合成为一个氢原子。 |
This repulsion and attraction (force between stationary charged particles) is known as the Electrostatic Force and extends theoretically to infinity, but is diluted as the distance between particles increases. |
这种排斥和吸引(静止带电粒子之间的力)称为静电力。理论上讲,它会延伸至无穷远,但是会随着粒子间距离增大而减小。 |
When an atom has one or more missing electrons it is left with a positive charge, and when an atom has at least one extra electron it has a negative charge. |
当一个原子少了一个或者更多电子时,它带有正电荷。当原子有至少一个多余电子时,它则带有负电荷。 |
Having a positive or a negative charge makes an atom an ion. |
带有正电荷或负电荷使得原子成为离子。 |
Atoms only gain and lose protons and neutrons through fusion, fission, and radioactive decay. |
原子只通过聚变,裂变或放射性衰变来获得或失去质子和中子。 |
Although atoms are made of many particles and objects are made of many atoms, they behave similarly to charged particles in terms of how they repel and attract. |
尽管原子是由很多粒子组成,物体也是由很多原子构成的,他们在如何互相排斥和吸引这方面和带电粒子有相似的特性。 |
In an atom the protons and neutrons combine to form a tightly bound nucleus. |
在原子中,质子和中子结合,形成一个紧密的原子核。 |
This nucleus is surrounded by a vast cloud of electrons circling it at a distance but held near the protons by electromagnetic attraction (the electrostatic force discussed earlier). |
一个巨大的电子云围绕着原核。这电子云离原子核一定距离旋转,但是由于电磁吸引力(前面讨论的静电力)而离质子较近。 |
The cloud exists as a series of overlapping shells / bands in which the inner valence bands are filled with electrons and are tightly bound to the atom. |
电子云是一系列重叠的层/带组成的。其中内部的价带充满了电子,而且紧紧被原子束缚着。 |
The outer conduction bands contain no electrons except those that have accelerated to the conduction bands by gaining energy. |
除了那些已经获得能量而加速到导带的电子以外,外部的导带没有电子。 |
With enough energy an electron will escape an atom (compare with the escape velocity of a space rocket). |
如果有足够的能量,一个电子可以脱离原子的束缚。(和太空火箭的逃逸速度类似) |
When an electron in the conduction band decelerates and falls to another conduction band or the valence band a photon is emitted. |
一个在导带的电子减速并掉入另一个导带或者价带时,一个光子会被释放出来。 |
This is known as the photoelectric effect. |
这被成为光电效应。 |