| Atoms, the smallest particles of matter that retain the properties of the matter, are made of protons, electrons, and neutrons. |
原子，即维持物质性质的最小粒子，由质子、电子和中子组成。 |
| Protons have a positive charge, Electrons have a negative charge that cancels the proton's positive charge. |
质子带有正电荷，电子带有负电荷从而抵消了质子的正电荷。 |
| Neutrons are particles that are similar to a proton but have a neutral charge. |
中子是类似质子的粒子，但有中性电荷。 |
| 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. |
同种电荷互相排斥，异种电荷互相吸引，除此之外，正、负电荷之间没有什么差异。 |
| If a solitary positive proton and negative electron are placed near each other they will come together to form a hydrogen atom. |
如果一个孤立的正质子和负电子相互靠近，它们就会聚集在一起形成氢原子。 |
| 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）被称为静电力，理论上讲这种力可以无限延伸，但随着粒子之间距离的增加而减弱。 |
| 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. |
当一个原子失去一个或多个电子时，它会带有一个正电。当一个原子至少有一个额外的电子时，它就带有一个负电荷。 |
| Having a positive or a negative charge makes an atom an ion. |
带有正电荷和负电荷的原子就成为离子。 |
| Atoms only gain and lose protons and neutrons through fusion, fission, and radioactive decay. |
原子通过聚变、裂变和衰变才会增加或者失去质子和中子。 |
| 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. |
虽然原子是由许多粒子组成的，而物体是由许多原子组成的，就排斥和吸引的方式而言却是相似的。 |
| 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结合的核。 |
| 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). |
这个原子核被巨大的电子云包围着。电子云与原子核相隔一定距离，但通过电磁引力（就是之前提到的静电力）聚集在质子附近。。 |
| 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. |
电子云以重叠壳状或带状的形式而存在，里面的内价带充满了电子，并与原子紧密地结合在一起。 |
| The outer conduction bands contain no electrons except those that have accelerated to the conduction bands by gaining energy. |
而外导带却不包含电子除了那些通过增加能量而加速到导带部分的电子。 |
| With enough energy an electron will escape an atom (compare with the escape velocity of a space rocket). |
没有能量电子会逃离原子（和空间火箭的逃逸速度作比较） |
| When an electron in the conduction band decelerates and falls to another conduction band or the valence band a photon is emitted. |
当电子在导带减速下降到另一个导带或价带时，就会发射出光子。 |
| This is known as the photoelectric effect. |
这就是所谓的光电效应。 |
