Alevel化學課程是一度被評為最難的Alevel課程之一的一門，在IGCSE階段，有很多同學對化學這門科目的學術性和實踐性難度都有所了解。它的知識點數(shù)量多且細碎，有很多原理、概念和公式需要記憶，本篇中，我們留求藝留學為大家?guī)淼氖茿S階段的基礎知識原子核結構的相關內(nèi)容，一起來看看吧！

The nucleus 原子核

The protons and neutrons in each atom are tightly packed in a positively charged nucleus. Negatively charged electrons move around the nucleus. The number of protons in a nucleus defines the type of atom and is the same as the atomic number. The number of neutrons is found by subtracting the atomic number from the mass number. In an atom because there is no overall charge the number of electrons equals the number of protons.

每個原子中的質子和中子都緊緊地擠在一個帶正電的原子核中。帶負電的電子在原子核周圍移動。原子核中的質子數(shù)決定了原子的類型，與原子數(shù)相同。中子的數(shù)量是通過從質量數(shù)中減去原子數(shù)而得到的。在一個原子中，由于沒有整體電荷，電子數(shù)等于質子數(shù)。

In chemical reactions, the nucleus remains unchanged.

在化學反應中，原子核保持不變。

Geiger and Marsden bombarded a thin gold foil with a beam of alpha particles.

蓋格和馬斯登用一束α粒子轟擊薄薄的金箔。

Most of the particles passed through the foil without deflection and were detected by a flash of light when the alpha particle struck a zinc sulphide screen, surrounding the gold foil.

大多數(shù)粒子在沒有偏轉的情況下通過了金箔，并在α粒子擊中金箔周圍的硫化鋅屏幕時被一道閃光檢測到。

A few were deflected and some of these were deflected at angles greater than 900, suggesting they had been repelled by large positive charges within the foil - nuclei of atoms of gold.

少數(shù)粒子被偏轉，其中一些被偏轉的角度大于900，這表明它們被金箔內(nèi)的大型正電荷--金原子核--所排斥。

Arrangement of electrons around the nucleus 電子圍繞原子核的排列方式

From GCSE you should be familiar with the Bohr model of electrons arranged around a nucleus. The electrons are in certain?energy levels and each energy level can hold only up to a maximum number of electrons.

從GCSE開始，你應該熟悉電子圍繞原子核排列的玻爾模型。電子處于一定的能級，每個能級只能容納最多的電子數(shù)。

A sodium atom containing 11 electrons has an electron arrangement of 2,8,1. Two electrons filling the first shell, eight electrons filling the second shell and one electron in the outer third shell.

一個含有11個電子的鈉原子的電子排列是2,8,1。兩個電子填充第一層外殼，八個電子填充第二層外殼，一個電子在外面的第三層外殼。

However, these models of electron arrangement are simple and a more advance done can now be used. It is possible to break these energy levels into?sub-shells.

然而，這些電子排列的模型是簡單的，現(xiàn)在可以使用一個更先進的完成。有可能將這些能級分解成子殼。

Electrons are impossible to locate exactly at any one time. It is however, possible to indicate a region or volume where the electron is most likely to be found. This region is called an?Orbital.

電子在任何時候都不可能被準確定位。然而，有可能指出電子最有可能被找到的一個區(qū)域或體積。這個區(qū)域被稱為 "軌道"。

Each orbital is capable of holding a maximum of 2 electrons. Orbitals can be divided intos, p, d, and ftypes. Each type has its own characteristic shape.

每個軌道最多能夠容納2個電子。軌道可以分為s、p、d和f類型。每種類型都有自己的特征形狀。

【微語】你在遠方的校園里, 用知識點亮未來, 用堅韌書寫青春的華章。