| Atoms, the smallest particles of matter that retain the properties of the matter, are made of protons, electrons, and neutrons. |
原子是保留了物质性质的最小的粒子，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. |
质子携带一个正电荷，电子携带一个负电荷，能够抵消质子的正电荷。 |
| Neutrons are particles that are similar to a proton but have a neutral charge. |
中子与质子相似，但它是电中性的。 |
| 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. |
携带相同电荷的粒子会相互排斥，携带相反电荷的粒子相互吸引，除此之外，正电荷与负电荷之间并没有区别。 |
| If a solitary positive proton and negative electron are placed near each other they will come together to form a hydrogen atom. |
如果一个孤立的携带正电荷的质子和一个携带负电荷的电子离得很近，那么它们就会结合，形成一个氢原子。 |
| 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. |
这种排斥力和吸引力（携带静电荷的粒子之间的力）被称为静电力，理论上它的作用范围可以延伸到无穷远，但随着粒子之间距离的增大而减小。 |
| 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. |
当原子缺失了一个以上的电子，它就携带正电荷；如果它额外携带了一个以上的电子，它就携带负电荷。 |
| Having a positive or a negative charge makes an atom an ion. |
携带正电荷或负电荷的原子就成了离子。 |
| Atoms only gain and lose protons and neutrons through fusion, fission, and radioactive decay. |
原子只能通过聚变反应、裂变反应和辐射衰变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. |
尽管原子由许多粒子组成，而物体又由许多原子组成，在吸引或排斥带电粒子方面，它们都具有相似的性质。 |
| In an atom the protons and neutrons combine to form a tightly bound nucleus. |
在原子里，质子和中子紧密结合，形成原子核。 |
| 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). |
原子核被一团电子云包围着。电子云被质子产生的电磁力吸引，在离原子核一定距离的地方围绕它旋转（静电力参见上文）。 |
| 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. |
电子云以一系列相互重叠的壳层（或电子带）形式存在，内侧价带上的电子与原子核紧密联系。 |
| The outer conduction bands contain no electrons except those that have accelerated to the conduction bands by gaining energy. |
外层的传导带上一般没有电子，只有那些获得能量的电子才能加速进入传导带。 |
| With enough energy an electron will escape an atom (compare with the escape velocity of a space rocket). |
如果获得了足够的能量，电子可以逃离原子核（参考火箭的逃逸速度）。 |
| When an electron in the conduction band decelerates and falls to another conduction band or the valence band a photon is emitted. |
当传导带上的电子减速，落入另一层传导带或价带，就会释放一个光子。 |
| This is known as the photoelectric effect. |
这就是光电效应。 |
