中４科化學問題

好簡單
ionic bond和covalent bond係化學鍵既一種
化學鍵是甚麼呢?
兩種物質能夠組成化合物便是有化學鍵
eg.NaCl 就是有化學鍵將Na和Cl結合在一起
ionic bond是離子鍵
covalent bond是共價鍵
還有一種是金屬鍵

ionic bond是存在於金屬與非金屬之間的''力''
covalent bond是存在於非金屬與含有非金屬化合物之間的''力''
這樣解釋比較清楚

An ionic bond is the strong electrostatic forces of attraction between oppositely charge ions

An ionic bond is formed when one or more eletrons are transperred form one atom(or a groupof atoms) to another

When a metal and a non-metal combine to form an ionic compound, atoms of the metal is usually release electrons while atoms of the non-metal usually gain electrons

For example,Calcium(metal) + Sulphur(non-metal) Calcium's electronic arrangement is 2,8,8,2 it tend to loss two electrons to become stable by having the same electron number of noble gas and Sulphur's electronic arrangement is 2,8,6 which tend to gain two electrons to become stable,therefore Calcium + Sulphur form a stable ionic compound CaS

Convalent bond is formed when one or more pairs of outermost shell electrons are shared between two atoms

A covalent bond is the strong electrostatic forces of attraction between the shared electrons and the two positively charged nuclei of the bonded atoms

the pair of electrons shared between two atoms is called bond pair electrons

For example hydrogen + chlorine, in order to obtain stable electronic arrangements, one hydrogen atom combines whit one chlorine atom.
Therefore, hydrogen + chlorine form a stable covalent compound HCl

2006-12-01 22:48:26 補充：
Covalent 係non-metal加non-metal ionic 係metal加non-metal

離子鍵只有在離子化合物中存在,可以互相吸引,便到離子間的力量更大。
共價鍵是共價化合物中的強大力量。 要如何分辨,都只是看是否離子/共價化合物便能分辦。